Sweet Potatoes au Gratin with Gruyere, Parmesan, and Pecan Topping Recipe
Sweet Potatoes au Gratin is a rich and creamy baked dish featuring thinly sliced sweet potatoes layered in a savory cheese sauce made from Gruyere, Parmesan, butter, and heavy cream, flavored with garlic, shallots, thyme, and nutmeg, topped with toasted pecans for a delightful crunch.
- Prep Time: 15 minutes
- Cook Time: 50 minutes
- Total Time: 65 minutes
- Yield: 6 servings 1x
- Category: Side Dish
- Method: Baking
- Cuisine: French-inspired
Ingredients
Scale
Vegetables
- 4 sweet potatoes (around 1400g)
- 1 shallot
- 1 clove garlic
- 3 sprigs fresh thyme
Dairy
- 1 tbsp butter
- 350 ml heavy cream
- 150 g grated Gruyere cheese
- 20 g grated Parmesan cheese
Spices & Nuts
- 1 tsp nutmeg
- salt (to taste)
- black pepper (to taste)
- 20 g roughly chopped pecans
Instructions
- Prepare the sweet potatoes: Wash and peel the sweet potatoes thoroughly to remove any dirt and skin.
- Preheat the oven: Set your oven to 425°F (220°C) to get it ready for baking.
- Slice the sweet potatoes: Using a mandoline set to approximately 4 millimeters, carefully cut the sweet potatoes into thin, even slices.
- Arrange the slices: In a cast-iron pan or any oven-safe dish, arrange the sliced sweet potatoes in a spiral pattern. Use smaller slices at the bottom so the arrangement looks uniform and even.
- Prepare the sauce base: Finely dice the shallot and garlic, then strip the thyme leaves from their stems. Heat butter in a pan and sauté the shallot, garlic, and thyme leaves for a few minutes until fragrant.
- Make the cheese sauce: Add heavy cream, half of the grated Gruyere, and all the Parmesan cheese to the pan. Stir continuously until the cheese melts smoothly into the cream. Season the sauce with nutmeg, salt, and black pepper to taste, and let it simmer for a couple more minutes until it begins to thicken.
- Combine and bake: Pour the warm cheese sauce evenly over the arranged sweet potatoes in the dish. Place in the preheated oven and bake for about 45 minutes until the sweet potatoes are tender and the top is golden brown.
- Add pecans to toast: Approximately 5 minutes before baking is complete, sprinkle the roughly chopped pecans on top to toast them lightly.
- Garnish and serve: Optionally garnish with a fresh sprig of thyme. Serve the gratin warm and enjoy this comforting dish!
Notes
- Using a mandoline ensures the sweet potato slices are evenly thin, helping them cook uniformly.
- Gruyere cheese offers a nutty, creamy flavor, but you can substitute with Swiss cheese if unavailable.
- Be sure to watch the pecans closely when toasting towards the end to prevent burning.
- This dish pairs well as a side for roasted meats or vegetarian mains.
- Leftovers can be refrigerated and gently reheated in the oven to preserve texture.
Keywords: Sweet Potatoes au Gratin, Sweet Potato Gratin, Cheese Gratin, Baked Sweet Potatoes, Gruyere Cheese Dish, Comfort Food, Side Dish, Oven-Baked Sweet Potatoes
