Sweet Potatoes au Gratin (GF)

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Sweet Potatoes au Gratin 4

When I look at most of my holiday dinners,  many are of the meat and potato variety. (OK, there’s more likely to be pasta or polenta on the table but they do start with a “p” and that should qualify them.)  Up until several years ago, those potatoes were either mashed or baked au gratin. That’s when I decided enough with the plain potatoes. Sorry, Idaho. Bring on the sweet potatoes!

Initially, I made them as I would my potatoes au gratin: with milk, Swiss cheese, and a little butter. Over time, I swapped out some of the ingredients and in the process these potatoes earned a standing invite to my holiday tables.

The recipe below is the latest version. Earlier editions included  pancetta, bacon, garlic, and/or nutmeg. Although I liked each, the individual flavors worked better with normal potatoes, their flavors being a bit too much for the sweet potatoes. You may feel that way about the onions used here. If too much for your tastes, substitute diced shallots in their place.

One more thing to remember. Do not bring these potatoes from the oven directly to the table for serving. They really do need to sit for no fewer than 10 minutes — 15 is better — so that they set. You want to serve creamy potatoes not a runny mess.

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Sweet Potatoes au Gratin 3

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Sweet Potatoes au Gratin Recipe

Ingredients

  • butter or cooking spray
  • about 1,5 lbs. (680 g) sweet potatoes, peeled and sliced (See Notes)
  • 1 medium onion, thinly sliced
  • 5 to 6 oz (140 – 170 g) Gruyère cheese, grated  (Swiss, Fontina, or Emmental, among others, may be substituted)
  • 6 oz (118 ml) heavy cream
  • 3 tbsp arrowroot (flour or cornstarch may be substituted)
  • 1 tbsp butter, cut into 8 pieces
  • 1/4 c (25 g) grated Parmigiano Reggiano (Pecorino Romano may be substituted)
  • salt and pepper to taste

Directions

  1. Use cooking spray or a tab of butter to liberally grease an oven-proof baking dish.
  2. Make a slurry using 1/2 of the heavy cream and the arrowroot. Once thoroughly combined, add the remaining cream, stir, and set aside,
  3. Pre-heat oven to 375˚ F (190˚ C).
  4. Use 1/3 of the sliced sweet potatoes to create a layer covering the bottom of the baking dish,
  5. Cover that layer with 1/2 of the sliced onion.
  6. Season lightly with salt and pepper.
  7. Use 1/3 of the grated Gruyère to cover the onions and potatoes.
  8. Repeat steps 4, 5, and 6. using all the remaining onion in the process.
  9. Use the last of the sweet potatoes to cover the dish’s contents.
  10. Stir the cream slurry before pouring it evenly over the top of the dish.
  11. Cover the dish with the remaining Gruyère.
  12. Season lightly with salt and pepper.
  13. Dot the surface with the butter pieces.
  14. Sprinkle the grated Parmigiano Reggiano to evenly cover the entire dish.
  15. Bake in a pre-heated oven for 45 to 50 minutes or until the potatoes are nicely browned.
  16. Allow to rest at least 10 minutes before serving.

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sweet-potatoes-au-gratin-1

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Notes

I used a 9 inch (23 cm) square baking dish and the potatoes weren’t sliced too thinly. (.15 inches, 4 mm). More or less of the posted ingredients may be needed if the size of your baking dish differs appreciably from the one used here.

The recipe, as written, is gluten-free. If you haven’t arrowroot but wish to keep it GF, add an equal amount of cornstarch into the cream. Of course, if you and your guests have no issues with gluten, flour can be used as the thickening agent.

WIth its heavy cream, butter, and cheeses, this is not a low-calorie dish. (That’s why I only serve it on special occasions and holidays.) If you’re looking for something a little more waist and heart-friendly, hop on over to Fanny Reggiori’s blog, foodidies, where she recently posted a delicious, lighter sweet potato au gratin recipe. No matter the recipe you choose to prepare, you really cannot go wrong.

Since we’re talking healthy, which do you think is healthier, baking potatoes or sweet? Click HERE to find out. And if that kind of info floats you boat, go HERE to see a list of similar comparisons. Some of the results may surprise you.

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It’s déjà vu all over again …

standing-rib-roast-deja-vu

Since we’re talking holidays, here’s a look back at the method I use to prepare standing rib roast every New Year’s Day. You can catch a glimpse of one in the first photo of this post.) It’s easy to prepare but much depends upon aging the roast in your fridge before cooking it. Interested? You can learn all about it HERE.

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Coming soon to a monitor near you …

hot-pepper-relish-preview

Hot Pepper Relish

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87 thoughts on “Sweet Potatoes au Gratin (GF)”

  1. Unfortunately, the rest of my family doesn´t like sweet potatoes as much as I do. I´ve made sweet potato gratin before, using the classic French approach with just cream, garlic and nutmeg, but perhaps I can win them over with your cheesy version! At least it made me instantly hungry for dinner (and it´s 9 a.m. here ;-))!

    Liked by 1 person

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    • Yeah, the cheese in this dish is really good! You Moms are in a tough position. Mine loved a few dishes that the rest of the family didn’t, like split pea soup, for example. Lucky for her, I enjoyed it, too, and it became a special meal for just the two of us when no one else was home. 🙂

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  2. buongiorno amico John, ti ho riservato una piccola sorpresa nel post SanGimignano 2, quando vuoi dalle un’occhiata grazie!
    Anche io amo le patate al forno, ma molto più dietetiche delle tue, addirittura anche senza olio, pure vengono ok ( 🙂 ) queste grandi ricette impegnano molto ( anche la digestione ha ha ) ma sono ottimissime e mi ripropongo, dopo una settimana di quasi digiuno di sperimentarle!
    sempre grata dei tuoi post, ti invio un carissimo saluto
    Annalisa

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    • I have just returned from your San Gimignano post, Annalisa. You are so kind to dedicate it to me. I now know that I must visit San Gimignano the next time I come to Italy, I do not wish to ignore your kindness. 🙂
      Yes, these potatoes are delicious but I cannot prepare them very often. I do not fast very well and fear that I would grow very large. 😀
      Take care, my friend. One day I hope we can meet in Italy.

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  5. That looks very tempting but you had me at cream and cheese. I like sweet potatoes in a Goan-style curry or tossed with oil and spices and roasted, but it’s never occurred to me to make a gratin. It’s going on the list. Lx

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    • Oh, yes, Linda. Do put this on the list. You won’t be disappointed. I always make more than enough for the dinner. I won’t be making it again until another celebration, so, I make sure there are some leftovers around for at least another helping.

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  9. Good reminder to let gratins sit a bit before serving. They do need to firm up, although I’m OK with a less-than-firm gratin. I’ve made sweet potato gratins before, but never exactly like this. Gotta give it a try! Looks wonderful. And we LOVE sweet potatoes at our house! Thanks so much.

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    • It only takes one premature serving of a gratin to learn to let that dish set for a spell. Nothing more disappointing than seeing such a beautiful dish turn ugly within a couple minutes. I, too love sweet potatoes and was on quite a kick for a while there, after I got my spiralizer. Sweet potato shoestring potatoes are really quite good — and addictive. (I really need to post that recipe!) As always, John, thanks for your kind words.

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  10. Do you realize how grateful I am for your posts?
    Even makes my house smell better when I open up your blog in the morning.
    Thank you Thank you!!!

    And you can bet I am going to make this sweet / savory dish—after all, I know it’s tried + true.
    Thanks again.
    Happy Thanksgiving!
    Teri
    Oregon
    x-x-x-x-x-x

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    • That’s a very kind thing to say, Teri. Thank you. I’ve been told that 2 others have prepared these potatoes and received rave reviews. Sweet potatoes, cheese, and heavy cream. What’s not to like?
      Happy Thanksgiving!

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    • Thanks, Gerlinde. It’s tough when you like a dish that your spouse or kids don’t. Luckily, my tastes were very similar to Mom’s. She would save those dishes for when it was just the 2 of us at the table and we’d feast!
      Hope you have a very Happy Thanksgiving!

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  15. Although our Thanksgiving is long over, this has given me food for thought in planning our holiday dinner. I love sweet potatoes- and I’m always looking for new ways to do them up. Hope you have a wonderful holiday, John!

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    • Thanks, Cole, and good to see you here again…
      Do give these a try. I seriously doubt that you’ll be disappointed. They’re that good!
      Apropos to nothing, how’s the housing market in your neck of the woods? 😉

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      • Lol. I’m not sure that last bit doesn’t have an underlying message… As a new homeowner here in Toronto, myself, I’d recommend you jump right in if you’re thinking about it. We’re already low on stock, and I have a feeling that demand is probably even higher since, oh, about two weeks ago 😉

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    • I’m a little behind and I now know that you’ve prepared and enjoyed this dish. I’m so glad that you did! For several years now, it wouldn’t be Thanksgiving here without these potatoes and it’s one serving dish guaranteed to be empty when the table is cleared.
      Hope you all enjoy a fantastic Thanksgiving, Gretchen!

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    • I so agree, Mar. If it’s a celebration, these potatoes are on the table and always get rave reviews. I, also, agree about Thanksgiving. I’d very much prefer it celebrated earlier, as you do to the North. It’s supposed to be a Day of Thanks, not Black Friday Eve.

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  20. Such a festive recipe, John, I just love the colour of the sweet potatoes and the gratin on top. It’s difficult not to lick one’s lips while reading through the recipe.
    I just made a Aubergine Parmigiana for dinner and it too had to rest to reabsorb the liquid and thicken up. It’s made with pan seared eggplant dredged in corn starch, so it’s not nearly as heavy as the breaded and deep fried version; after all, I’d rather eat my calories from cheese as opposed to deep frying! It’s a recipe I followed from a chef’s website (we went on a cooking class here in Toronto last week and I liked the chef). I may revise the recipe a little bit and post it on my blog but for now, it’s going to be a challenge to ‘forget’ that leftovers are sitting in the fridge. Damn thing keeps calling my name.

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    • I know what you mean about leftovers calling your name, Eva. Luckily, there are rarely any of these potatoes left in the serving dish. My guests continue to go back to it until the dish is empty. If they didn’t, I know that I’d finish them off once the guests have all left. Load the dishwasher, grab a glass of wine, and settle back with this serving dish and a spoon. Aaaahhhh!
      I’ve quit breading and frying eggplant, too. I’ve got a post for eggplant lasagna coming up and the eggplant is sprayed with cooking spray and baked before using it in the recipe. For me, as it is for you, it’s all about the cheese! 😀

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  21. Boy, do I know about a runny mess! I admit, I have dug into a gratin too soon. Im loving all these sp recipes! Just came from John’s site where he had mashed with chipotle, and now here we have sp gratin.
    Great dishes to put in my dinner rotation. I can’t make this for Thanksgiving though…Trace is very particular about his sweet potato casserole..Southern style, a family recipe 🙂

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    • I think we’ve all gone down that road, Nazneen, and served a casserole of some sort too early. What a mess!
      Of all of our holidays, Thanksgiving seems to be the one most tied to certain recipes. When I hosted the dinner, some friends made requests for a favorite dish because it “wouldn’t be Thanksgiving without Mom’s …” For me, so long as there was a primo piatto of ravioli, I didn’t really care. I’d make whatever they wanted. 🙂
      I hope you have a very happy Thanksgiving!

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  22. John – MY DARLING!! I’ve been out of touch for sooo long. For many reasons… I’ve been having some health problems which are being straightened out. Nothing major… things like a low thyroid (hypothyroidism) and a bit of hypoglycemia. The doctor said I have a very small ‘tipping’ point’ with my sugar levels – then I get weak etc.
    Plus – I’ve been getting my beautiful yellow farmhouse ready to sell – which has been a lot of work, as you can only imagine. I have so many things I’ve had to go through.. plus making sure that everything – inside and out – is in good shape. (My cellar is NOT finished…. but the barn and attic have been gone through.)
    As always, I love, love, love your recipe. And I still have in the back of my mind to come out to Chicago in the not-so-distant future so we can hang out and have a ball. And… perhaps… do some cooking!! ; o )

    Liked by 1 person

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    • So glad to see you, Cecille. I’ve just checked and my subscription for receiving your posts was shut off!!!! It’s all set now and I’ll be making regular visits to your place again. Sorry that I didn’t notice.
      Also sorry to hear that you’ve had some health issues. May they continue to get “straightened out’ for you. I do ot envy your moving. It takes me forever to clean a closet since I spend too much time reminiscing about the things stored there. I can only imagine what it must be like to have an entire house to go through. I know that I’ll be doing the same in a few years and keep telling myself to get started lest it become overwhelming. I’ll do it … tomorrow. 🙂
      I hope you have a wonderful Thanksgiving, my friend.

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  24. Buona Sera John! What a fantastic idea! Scalloped potatoes with sweet potatoes. Onions, cream and cheese what more could a girl want!!! Good tip on leaving the dish sit for 15 minutes to let it sit. However, I bet smelling this dish in the oven and the 15 minutes would feel like 15 “hours” of waiting to try this delicious dish.

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    • Buongiorno, BAM! Yes, all of the major food groups are represented in this single dish. (Well, pasta isn’t but it’s my primo piatto.) As for the 15 minute resting time, I find t best to put it somewhere out of sight. If it’s visible, if I don’t “have a taste”, one of my guests surely will. The microwave, with another dish in front of the door, is a good place. 😀
      Happy Thanksgiving to you and yours, Bobbi!

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    • I thought the same thing, Mandy, the first time I prepared this dish. Up until then I’d have 2 serving dishes of potatoes, one regular and one with sweet potatoes. Those days are gone. It’s sweet potato au gratin all the way!!!
      I believe you’re back home now and hope that you enjoyed every moment of your trip. 🙂

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  28. Count me in also as one who never thought to put sweet potatoes into an au gratin environment. Rather silly in that I love sweet potatoes and au gratin both. Do a large part of my sweet potato consumption over the fall/winter – for whatever reason – so a perfect time to give this a go. (Oh…the Idaho Potato Commission is on Line 1 for you John…something about wanting equal time on a future post…) 🙂

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  29. What? No marshmallow???!!! This is my kind of sweet potato dish. Americans don’t seem to understand that sweet potatoes are already sweet, and really lend themselves to onions and garlic, and especially cheese! Great recipe.

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  31. We make a white and sweet potato gratin with rosemary that’s amazing. Our friends call them “crack potatoes” because once you start eating them, you can’t stop. I imagine you get the same reaction, and I should try yours without the white potatoes. Happy Thanksgiving to you and yours!

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    • Rosemary? Really? I love rosemary and cannot wait to add it to my next batch of potatoes. You’re right about their “crack” aspect, too. It is one dish that I can guarantee will be emptied during dinner, no matter how many guests are seated. I hope that you, too, have a wonderful Thanksgiving, David.

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    • Oh, yeah, Stefan, there’s nothing low-cal about this dish. That’s why I ony prepare it for celebratory dinners. Any more often and I’d need to keep a portable defibrillator under my dining table.
      Thanks for the heads-up. It’s been corrected. 😉

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    • That’s wonderful! I’m so glad that you enjoyed the recipe and that it’s earned a spot on your holiday table. Thanks for taking the time to let me know and have a fantastic Thanksgiving!

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  34. Have you added Smell-O-Vision to your blog? Because I swear I could smell this dish cooking as I was reading the ingredients.

    I have never thought to make sweet potatoes this way, and I can easily think of half a dozen people who would fight to have seconds…me included!

    Thanks for sharing this!

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  35. I just brought bake a bag of Louisiana yams from our recent vacation and can’t wait to give this a try. I love a good au Gratin but have never made one with sweet potatoes. Looks awesome!

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  36. simply divine, caro Gianni… 🙂 gonna try your sweet potatoes “au gratin” asap, but NO cow lactose and gluten free… I guess it’ll be also yummy with almond milk and goat cheese… 🙂 now and then, I mix yams and potatoes into a delicious “purée”, made with coco or almond milk and a little nutmeg powder…
    * * *
    ciao amico, my very best and have a pleasant weekend! 🙂

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    • So sorry for the delayed reply, Mary …
      No, we never made the traditional minestrone, let alone a meatless version. I looked in a couple cookbooks and they, too, included meat. The meat — pork products — are used in the beginning of the cooking process for both the fat rendered and the flavor. None used smoked pork (bacon) probably because the smoke cam be so overpowering. If you like, I can send you these recipes. If you have a pork substitute that you like, feel free to use them. Just let me know. I promise to reply to you in a more timely fashion. 🙂

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      • Thanks, John will look her up. I’m constantly trying to please family members who are hopping on to the vegetarian bandwagon. There’s no retiring from this job.
        Even though I am only just realising what a cheek it was to expect it, I do so appreciate your helping me out.❤️

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