My Sweet Potato Gratin is easy to make and a delicious twist on the classic potatoes au gratin.Sweet potatoes are a great option for any fall or winter side dish and get even when layered a garlic-sage cream and nutty Gruyere cheese. A great savory side dish this sweet potato gratin pairs well with everything from roasted chicken to your holiday turkey or ham.
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This sweet potato gratin is a delicious Thanksgiving side dish and is a great alternative to a traditional sweet potato casserole or scalloped potatoes. For the best results you’re going to want to use a mandoline to ensure you get thin, even slices of your sweet potatoes. I also find that adding a bit of the cream mixture with each layer of sweet potatoes and cheese gives this gratin a great texture once baked.
For more great Thanksgiving recipes take a look at my Green Bean Casserole with Shallots, Corn Pudding and Hasselback Butternut Squash.
Ingredients
- Sweet potatoes
- Milk
- Heavy cream
- Garlic
- Fresh sage
- Kosher salt
- Ground black pepper
- Gruyere cheese
- Parmesan cheese
- Slice the sweet potatoes evenly. Aim for slices about ⅛-inch thick so they cook evenly. A mandoline makes this quick and easy, but a sharp knife works too.
- Switch up the cheese. Gruyère adds a nutty, savory flavor, but fontina or white cheddar also work well. Keep the Parmesan for a flavorful golden topping.
- Use half-and-half. Substitute 1½ cups of half-and-half for the ¾ cup milk and ¾ cup heavy cream.
- Try different herbs. Fresh thyme or rosemary makes a delicious alternative to sage. Start with a smaller amount of rosemary, since its flavor can be quite strong.
- Layer the sauce and cheese. Add a little cream mixture and cheese between each layer of sweet potatoes for the best flavor and texture throughout the gratin.
- Cover, then uncover. Baking covered helps the sweet potatoes become tender, while removing the foil for the final 30 minutes allows the cheese to brown and become golden
- Let it rest before serving. Allow the gratin to rest for about 15 minutes after baking. This gives the sauce time to settle.
How to Make Sweet Potato Gratin
Preheat the oven to 400 ℉ while you prepare the gratin. Add the cream, milk (alternatively you can use 1.5 cups of half and half), garlic, sage, salt and pepper to a saucepan. Over medium heat bring the cream mixture to a just to a simmer then remove the pan from the heat.
Peel the sweet potatoes and cut them into 1/8″ inch slices using a mandoline. In a small bowl lightly mix together the gruyere and parmesan to combine.
Grease the baking dish with butter. Arrange the sweet potatoes in an even layer and spoon over 2-3 tbsp of the cream mixture then sprinkle with some of the cheese, making sure to reserve about 1/3 of the cheese for the final layer. Repeat with the remaining potatoes, cream and cheese until you have about 5-6 layers. For the final layer press down on the sweet potatoes to ensure they are fully submerged in the cream mixture then top with the reserved cheese.
Cover with foil and bake for 30 minutes. Remove the foil and bake for an additional 30 minutes or until the cream is absorbed and the cheese is golden brown. Remove the gratin from the oven and allow is to cool for 15 minutes before serving.
Storage and Reheating
Allow leftover sweet potato gratin to cool, then transfer it to an airtight container or cover the baking dish tightly. Refrigerate for up to 3–4 days.
To reheat cover the gratin with foil and reheat in a 350°F oven until heated through, about 20–30 minutes for a larger portion. You can also reheat indiviual portions in the microwave.
If you like this Sweet Potato Gratin be sure to take a look at some of my other recipes!
Butternut Squash and Mushroom Risotto
Balsamic Maple Roasted Brussels Sprouts
If you make this Sweet Potato Gratin please be sure to leave a comment and/or give this recipe a rating! Be sure to follow me on Youtube, Facebook and Pinterest for my latest recipes. Also, if you do make this recipe please tag me on Instagram or Tiktok, I’d love to see what you guys are making!
Sweet Potato Gratin
Equipment
- 1 small sauce pan
- gratin or baking dish
Ingredients
- 2 pounds sweet potatoes peeled and thinly sliced
- 3/4 cup milk
- 3/4 cup heavy cream
- 2-3 cloves garlic minced
- 1 tbsp fresh sage chopped
- 1 tsp kosher salt
- 1 tsp ground black pepper
- 1 cup Gruyere cheese finely shredded
- 1/2 cup Parmesan cheese finely shredded
Instructions
- Preheat the oven to 400 ℉.
- Add the cream, milk (alternatively you can use 1.5 cups of half and half), garlic, sage, salt and pepper to a saucepan. Over medium heat bring the cream mixture to a just to a simmer then remove the pan from the heat.
- Peel the sweet potatoes and cut them into 1/8" inch slices using a mandoline. In a small bowl lightly mix together the gruyere and parmesan to combine.
- Grease the baking dish with butter. Arrange the sweet potatoes in an even layer and spoon over 2-3 tbsp of the cream mixture then sprinkle with some of the cheese, making sure to reserve about 1/3 of the cheese for the final layer. Repeat with the remaining potatoes, cream and cheese until you have about 5-6 layers. For the final layer press down on the sweet potatoes to ensure they are fully submerged in the cream mixture then top with the reserved cheese.
- Cover with foil and bake for 30 minutes. Remove the foil and bake for an additional 30 minutes or until the cream is absorbed and the cheese is golden brown. Remove the gratin from the oven and allow is to cool for 15 minutes before serving.
Nutrition
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Dana says
Made this as a side for roast chicken and it was a hit! Loved these cheesy sweet potatoes, will make again