Sweet Potato Au Gratin (Creamy & Cheesy Holiday Side)
If you’re dreaming up a holiday side dish that feels special without asking too much of you, this sweet potato au gratin is the kind of Thanksgiving side that brings cozy, cheesy comfort to any gathering! It has all the charm of a classic gratin with melty Gruyère, a golden brown top, and slow-baked tenderness, but with the natural sweetness of sweet potatoes that makes every bite feel warm and memorable. This savory, cheesy twist on the sweet potato dishes I grew up loving fits right in on any holiday table!
Servings: 12
Ingredients
- 3 sweet potatoes cut into 1/8 inch slices on mandolin slicer
- 1 3/4 cups heavy cream
- 4-5 cloves garlic minced
- 2 tbsp unsalted butter melted
- 1 1/2 cup gruyere cheese shredded
- 1/2 cup Gouda shredded
- 1/2 cup parmesan cheese shredded
- 2 tbsp fresh thyme
- salt and pepper to taste
Instructions
- Preheat your oven to 375°F
- In a saucepan, melt the butter over medium heat. Add the minced garlic and cook for a minute or two until fragrant—add in the heavy cream and season with salt and pepper. Heat for a couple of minutes. (This mixture will not be super thick. But the sauce gets thicker as it cooks due to the potato starch).
- Layer the sliced sweet potatoes in a greased baking dish. Season each layer with salt/pepper and thyme, and sprinkle with the 3 different types of cheese.
- Pour the cream mixture over each layer of the sliced sweet potatoes, ensuring that the potatoes are well coated. I usually do 3-4 layers. Make sure not to add too much to each layer.
- Sprinkle the remaining cheese mixture over the top of the dish.
- Cover the baking dish with aluminum foil and bake for about 45 minutes.
- Remove the foil and bake for an additional 15-20 minutes, or until the sweet potatoes are tender, and the top is golden brown and bubbling
Notes
Expert Tips & Troubleshooting
- If your cheese sauce looks grainy, the cream mixture got too hot. Keep the heat gentle when warming the cream so the dairy doesn’t separate before baking.
- Don’t worry if the cream mixture seems thin when you pour it in. As the dish bakes, the starch from the sweet potatoes thickens the sauce naturally.
- Slice the potatoes evenly for the best texture. Uneven slices can bake at different speeds.
- If the top browns too quickly, loosely tent the dish with foil.
- A watery gratin in other recipes usually comes from too much liquid per layer. This method avoids that by keeping layers lightly coated, not drenched.
Nutrition
Calories: 306kcal | Carbohydrates: 13g | Protein: 11g | Fat: 24g | Saturated Fat: 15g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 6g | Trans Fat: 0.1g | Cholesterol: 76mg | Sodium: 306mg | Potassium: 264mg | Fiber: 2g | Sugar: 4g | Vitamin A: 8884IU | Vitamin C: 4mg | Calcium: 332mg | Iron: 1mg