Cheesy Sweet Potato Gratin (Printable)
Rich gratin layered with sweet potatoes, golden onions, and melted cheeses baked until tender and golden.
# What You'll Need:
→ Vegetables
01 - 2 lbs sweet potatoes, peeled and thinly sliced
02 - 2 large yellow onions, thinly sliced
03 - 2 cloves garlic, minced
→ Dairy & Cheese
04 - 2 cups shredded Gruyère cheese
05 - 1 cup shredded sharp cheddar cheese
06 - 1 1/2 cups heavy cream
07 - 1/2 cup whole milk
08 - 3 tbsp unsalted butter
→ Seasonings
09 - 1/2 tsp dried thyme
10 - 1/2 tsp ground black pepper
11 - 1/2 tsp salt
12 - 1/4 tsp ground nutmeg
→ Optional Additions
13 - 1 tbsp all-purpose flour for thickening
14 - 2 tbsp chopped fresh chives for garnish
# How To Make It:
01 - Preheat oven to 375°F. Grease a 9x13-inch baking dish with butter or cooking spray.
02 - Melt 2 tbsp butter in a large skillet over medium heat. Add sliced onions and a pinch of salt. Cook, stirring frequently, until deeply golden and caramelized, about 20-25 minutes. Add minced garlic during the last minute and cook until fragrant.
03 - Combine heavy cream, whole milk, thyme, nutmeg, black pepper, and remaining 1 tbsp butter in a small saucepan. Heat over medium-low until steaming but not boiling. If using flour, whisk in until smooth to create a slightly thickened base.
04 - Arrange half the sweet potato slices in the prepared baking dish. Season lightly with salt. Spread half the caramelized onion mixture over the potatoes. Sprinkle with half the Gruyère and half the cheddar cheese.
05 - Repeat layering with remaining sweet potatoes, caramelized onions, and cheeses.
06 - Pour the warm cream mixture evenly over the layered ingredients, ensuring it seeps through all layers.
07 - Cover the dish tightly with aluminum foil. Bake for 40 minutes to allow potatoes to cook through.
08 - Remove foil and continue baking uncovered for 20 minutes, or until the top is golden brown and bubbly and potatoes are fork-tender.
09 - Let the gratin rest for 10 minutes before serving to allow layers to set. Garnish with fresh chives if desired.
# Tips from dashanddishes:
01 -
- The sweet cream and sharp cheese create this incredible velvety texture that somehow feels both indulgent and comforting
- Its one of those rare dishes that actually improves with a little resting time, making it perfect for dinner parties
02 -
- Sweet potatoes vary wildly in thickness so slice them as evenly as possible or some pieces will turn to mush while others stay crunchy
- The cream mixture might look like too much liquid but trust the process because the potatoes will absorb most of it while baking
03 -
- Sprinkle a little extra cheese between the middle layers not just on top for those irresistible cheese pulls
- Place a baking sheet on the rack below to catch any bubbly over spills before they hit your oven floor