A creamy potato gratin made with layers of potatoes and onions, topped with cheese and baked to golden perfection. This comforting dish is perfect for Thanksgiving or any special occasion.
1: Preheat the oven to 400°F.
2: Grease an oven safe baking dish with butter.
3: Peel and slice the potatoes and onion into thin slices and place them in the dish.
4: In a pan, heat butter.
5: Add flour and then slowly add milk, vigorously whisking to remove lumps.
6: Turn heat low and add salt, pepper, garlic powder, and half of the cheddar and mozzarella cheese.
7: Pour the sauce evenly over the potatoes and onions to cover them.
8: Cover the pan with foil and bake for 45 minutes.
9: After 45 minutes, add the remaining cheese and Parmesan cheese.
10: Return to the oven and bake for an additional 30-45 minutes or until the potatoes are done and golden brown on top.
11: Remove from the oven and garnish with fresh chopped parsley.
