Sweet Potato Gratin

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A Sweet Potato Gratin layered with Gouda, Thyme and Parmesan cheese! It’s the perfect fall/winter side dish.

Sweet Potato Gratin from www.whatsgabycooking.com (@whatsgabycookin)

We’re having a mega sweet potato moment in our house! Poppy is obsessed with them. Thomas is obsessed with them. I am obsessed with them. The amount we buy on a weekly basis is truly wild. They are one of the most versatile vegetables to cook with. I’ve made them into countless recipes here on WGC and today we’re turning them into a Sweet Potato Gratin!

If you know me, you know that sweet potatoes with marshmallows are a hard pass for me. But I LOVE having sweet potatoes in some form on the Thanksgiving table. This year, they are coming in the form of this gratin!

Sweet Potato Gratin from www.whatsgabycooking.com (@whatsgabycookin)

Layers of thinly sliced sweet potatoes mixed with 2 kinds of cheese, some heavy cream and seasonings makes this one of the easiest dishes to make!

Here’s what you need for the Sweet Potato Gratin:

  • Sweet Potatoes – any variety would be delish to be honest, but I prefer the orange variety. Peel the skin and you’re in business. I like to slice these with a mandolin to make it quick and uniform.
  • Heavy cream + Milk – this is the liquid that will help the potatoes cook
  • Salt, Pepper and Thyme – we need all of these to season these to perfection
  • Gouda – if you want aged gouda, be my guest…. but you need gouda to make this the ultimate sweet potato gratin!
  • Parmesan – to add a bit of saltiness!
Sweet Potato Gratin from www.whatsgabycooking.com (@whatsgabycookin)
Gouda Sweet Potato Gratin from www.whatsgabycooking.com (@whatsgabycookin)

Sweet Potato Gratin

5 from 3 votes
A Sweet Potato Gratin layered with Gouda, Thyme and Parmesan cheese! It’s the perfect fall/winter side dish.
Prep Time 15 mins
Cook Time 1 hr
Resting Time 15 mins
Total Time 1 hr 30 mins
Course Side Dish
Cuisine American
Servings 6 people


  • 3 sweet potatoes peeled and sliced 1/8 inch thick on a mandoline
  • Kosher salt and freshly ground pepper
  • 1 tsp fresh thyme roughly chopped
  • ½ cup parmesan cheese shredded
  • 1 1/2 cups shredded Gouda (I love the Roth Gouda wedges shredded
  • 3/4 cup milk
  • 3/4 cup heavy cream


  • Preheat the oven to 400 degrees and lightly grease a cast iron skillet.
  • Mix together the cream and milk and set aside.
  • In the skillet, arrange the potatoes in an even layer. Drizzle with a few tablespoons of the cream mixture and season with salt, pepper, thyme and dust with some of the cheeses. Repeat with the remaining potatoes and cream, seasoning with salt and pepper, to form 6-8 layers. Press down on the layers to totally submerge the sweet potatoes in the cream mixture and top with additional cheese if needed.
  • Cover and bake for 30 minutes. Remove the cover and continue baking until the cream has been absorbed, the potatoes are cooked through, and the top is browned, 30 to 45 minutes. Remove from the oven and let rest for 15 minutes before serving.


I highly recommend a mandolin. It’s very tough (and requires a super sharp knife!) to cut even slices by hand.

Nutrition Information

Calories: 460kcal | Carbohydrates: 27g | Protein: 21g | Fat: 30g | Saturated Fat: 19g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 8g | Cholesterol: 110mg | Sodium: 700mg | Potassium: 536mg | Fiber: 3g | Sugar: 8g | Vitamin A: 16932IU | Vitamin C: 3mg | Calcium: 605mg | Iron: 1mg

Photo by Matt Armendariz / Food Styling by Adam Pearson / Recipe by What’s Gaby Cooking


  1. Gaby, this looks incredible! I’ve always had gratin with regular potatoes, but I’ve never thought to try it with sweet potatoes, and after seeing this, I can’t wait! I love the gouda in this too. Yum!

  2. My mom asked me to bring something special this year (I thought green bean casserole WAS special mom?!?!) So this is what I’ll bring and hopefully impress her! Or I’ll make it for the Ugly Christmas sweater party I’m hosting next week and using my my new $200 artisan wood cutting board that I’m also giving away on my blog right now.

  3. On brand <3 haha. Also this is the perfect amount of jazzed up I'm looking for for Christmas with the in-laws.

    1. you can def make it ahead of time – I’d cover and bake at 350 until warmed through when you’re ready to reheat

  4. Hi you! We have a newly (partially) opened can of evaporated milk. Would that be ok to use or should I stick with regular milk? Happy Thanksgiving

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