Description
Indulge in this rich, creamy, and irresistible sweet potato au gratin, featuring tender sweet potatoes in a luxurious cheesy sauce with a golden-brown top. It’s the perfect side dish for any occasion.
Ingredients
- 3 lbs sweet potatoes, peeled and thinly sliced (about 1/8-inch)
- 4 tbsp unsalted butter
- 2 cloves garlic, minced
- 4 tbsp all-purpose flour
- 3 cups heavy cream
- 1 cup grated Gruyère cheese, divided
- 1 cup grated sharp cheddar cheese, divided
- 1/2 tsp salt, or to taste
- 1/4 tsp black pepper, or to taste
- Pinch of nutmeg
- Optional: 1 tbsp light brown sugar (for extra sweetness, if desired)
Instructions
- Preheat oven to 375°F (190°C). Grease a 9×13-inch baking dish.
- Arrange sliced sweet potatoes on paper towels to absorb moisture.
- In a medium saucepan, melt butter over medium heat. Add garlic and cook 30 seconds until fragrant.
- Whisk in flour and cook for 1-2 minutes, stirring constantly, to create a roux.
- Gradually whisk in heavy cream until smooth. Bring to a gentle simmer, then reduce heat to low.
- Stir in 3/4 cup Gruyère and 3/4 cup cheddar until melted and smooth. Season with salt, pepper, and nutmeg (and optional brown sugar).
- Layer one-third of the sweet potato slices in the prepared baking dish. Top with one-third of the cream sauce. Repeat layers twice more, ending with a final layer of sauce.
- Sprinkle the remaining 1/4 cup Gruyère and 1/4 cup cheddar over the top.
- Cover the baking dish loosely with aluminum foil and bake for 30 minutes.
- Remove foil and bake for another 25-35 minutes, or until sweet potatoes are fork-tender and the top is golden and bubbly.
- Let rest for 10-15 minutes before serving to allow the sauce to set.
- Prep Time: 20 mins
- Cook Time: 60 mins