Ingredients
Scale
- 2 T salted butter
- ½ sweet onion, peeled and chopped small
- 2 cloves garlic, peeled and minced
- 3 tsp fresh thyme leaves, divided
- 2 T flour
- 1.5 cups whole milk
- 1 cup extra sharp cheddar
- ½ cup gruyere, divided
- 2 lbs sweet potatoes, peeled and thinly sliced (approx. eighth of an inch)
- 1.5 cups diced ham
- Salt and pepper to taste
- Cooking spray
Instructions
- Preheat oven to 375 degrees. Grease an 8×8 casserole or glass baking dish with cooking spray.
- Melt butter in a heavy bottomed pan over medium heat. Add the onions, garlic, and 2 tsp of thyme leaves. Cook, stirring frequently, for about 4-5 minutes, until onions are soft and translucent. Add flour to pot, cook and stir for one minute. Slowly pour in the milk, whisking vigorously to prevent lumps. Reduce heat to low and cook sauce for about 5 minutes, whisking frequently. Add all the sharp cheddar and half of the gruyere to the pan. Cook and stir until cheese is melted. Remove pan from heat. Taste sauce and adjust seasonings.
- Layer half of the sliced sweet potatoes in the glass baking dish. Top with all of the diced ham. Pour half of the sauce over the sweet potatoes and ham. Layer the remaining sweet potatoes on top and pour on the rest of the sauce. Cover the baking dish with foil. Place in the preheated oven and bake for 50 minutes.
- Remove the baking dish from the oven. Remove foil and sprinkle the remaining gruyere over the potatoes. Return pan to oven and bake for an additional 20 minutes, until the cheese is melted and the potatoes are turning golden brown. Sprinkle the remaining teaspoon of thyme over the top of the potatoes and serve.