If you want a flavorful, healthy side dish that goes with everything, you need to try this dairy-free, AIP-compliant Sweet Potatoes Au Gratin! It is made with healthy sweet potatoes and a creamy sauce that tastes cheesy, yet is vegan and dairy-free.

This side dish takes just a few minutes to prepare and tastes hearty and delicious. It is AIP-friendly and suitable for those following a Paleo diet.

Sweet Potato Au Gratin

In this recipe, I chose to use sweet potatoes instead of white potatoes because sweet potatoes are a much healthier choice. They are loaded with beta-carotene and antioxidants, and are not inflammatory like nightshade white potatoes. Sweet potatoes are high in fiber, vitamin C, manganese, vitamin B6, and potassium. All of these nutrients are good for the body: Beta carotene supports healthy vision, fiber helps promote gut health, vitamin C promotes a healthy immune system, manganese is good for the metabolism, and potassium is important for healthy blood pressure. 

Luckily, sweet potatoes are not only healthy, but they also taste really good paired with a coconut-based dairy-free sauce!

https://www.amymyersmd.com/recipe/sweet-potatoes-au-gratin/ Birds eye view of ingredients such as sweet potato, rosemary, garlic, and coconut yogurt in separate bowls

Dairy-free Au Gratin Sauce

The sauce for this sweet potato au gratin is made with coconut milk and coconut yogurt as the base. Coconut milk is rich in electrolytes and antioxidants. Electrolytes help regulate fluids in the body, while antioxidants help prevent the effects of aging and tumor growth. Coconut milk also contains iron, which is important for preventing anemia, and has anti-inflammatory properties.

Coconut yogurt is used to thicken the sauce, along with a little cassava flour. I add a little turmeric to the sauce to give it a cheesy yellow color and to add extra antioxidants, since turmeric is very high in antioxidants! The sauce is seasoned with thyme and sage, as well as nutritional yeast. Nutritional yeast is a great addition to sauces because it gives them a cheesy flavor without adding any gut-irritating dairy, and it is loaded with essential amino acids and B vitamins, which are essential for healthy cell function, energy levels, and brain function. 

https://www.amymyersmd.com/recipe/sweet-potatoes-au-gratin/ Hand pouring cassava flour into skillet full of sauce

How to make Sweet Potato Au Gratin

To make sweet potato au gratin, start by thinly slicing sweet potatoes, either with a knife or with a mandoline slicer. Try to make the slices as even as possible, about ⅛- or ¼-inch thick.

Then make the sauce by whisking together coconut milk, coconut yogurt, sea salt, fresh thyme leaves, freshly chopped sage, turmeric, cassava flour and nutritional yeast. In a saucepan, heat the sauce until it just starts to simmer and thickens to your liking.

Arrange the sweet potato slices in an 8×8-inch baking casserole, slightly overlapping. Pour some sauce on top, then add another layer of sweet potatoes. Continue until you have 3-4 layers of sweet potatoes, or as many as you can fit in the pan. Pour the rest of the sace on top. 

https://www.amymyersmd.com/recipe/sweet-potatoes-au-gratin/ Sliced sweet potatoes covered with sauce in a glass baking pan

Cover with foil and bake at 400 degrees fahrenheit for 35-40 minutes, or until the sweet potatoes are fully cooked. Carefully remove the foil and broil for 1-2 minutes, or until the tops of the sweet potatoes are golden brown.

These sweet potatoes au gratin make a great side dish for any protein, such as  grilled steak, maple dijon salmon, or baked chicken legs.

https://www.amymyersmd.com/recipe/sweet-potatoes-au-gratin/ Baked sweet potatoes au gratin fresh out of the oven

Other sweet potato recipes to try:

Sweet Potatoes Au Gratin

Sweet Potatoes Au Gratin

Sweet Potatoes Au Gratin



6 servings

6 servings

Prep Time

10 minutes

Cook Time

50 minutes

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  • 2 908 lbs g sweet potato
  • 1 240 cup ml coconut milk
  • 1 4.929 tsp ml garlic powder
  • 1 4.929 tsp ml onion powder
  • 1/2 2.4645 tsp ml ground turmeric
  • 1 4.929 tsp ml sea salt to taste
  • 2 29.574 tbsp ml Cassava flour
  • 2 29.574 tbsp ml Nutritional yeast
  • 3/4 180 cups ml plain coconut yogurt
  • 1 14.787 tbsp ml thyme or 1 tsp dried thyme



  1. Preheat oven to 400 degrees Fahrenheit.
  2. Use a mandoline slicer to thinly slice the sweet potatoes. Make sure to use cut-resistant gloves to protect your hands!
  3. In a medium saucepan, combine the coconut milk with the garlic powder, onion powder, turmeric, sea salt, and cassava flour. Whisk together and cook over medium heat until the mixture has thickened, about 5 minutes. There is no need to bring the mixture to a boil.
  4. Remove from heat and add the nutritional yeast, coconut yogurt, and thyme leaves, and stir until no lumps remain. Carefully taste and adjust the seasonings, if needed.
  5. Add a layer of the sliced sweet potatoes in an 8x8 inch baking dish, spooning a few tablespoons of sauce over the sweet potatoes. Add another layer or two of sweet potatoes and sauce - as many as your baking dish will allow. Pour the rest of the sauce over the top layer of the sweet potatoes. Sprinkle additional fresh thyme on top.
  6. Cover the baking dish with foil and bake in a preheated oven at 400 degrees for 35-40 minutes, or until the sweet potatoes are fully cooked and tender when pierced with a fork. Remove the foil and broil the top of the sweet potatoes for 1-2 minutes, taking care not to burn the potatoes. Allow to cool for a few minutes and serve warm with your protein of choice.