- Cook Time
- Prep Time
- 5 tablespoons butter
- 3 onions, chopped
- Salt and pepper
- 1/2 cup flour
- 5 cups milk, warmed
- 1 1/4 cups grated parmesan cheese
- 3 pounds baking potatoes, peeled
- 1 pound sweet potatoes, peeled
- 1 11 ounce log fresh goat cheese, crumbled
- 2 ounces chopped spinach, thawed and squeezed dry
Position a rack in the upper third of the oven and preheat to 425 degrees . Grease a 4-quart casserole dish. In a large skillet, melt 4 tablespoons butter over medium heat. Add the onions, 2 teaspoons salt and 1/2 teaspoon pepper and cook, stirring, for 6 minutes. Stir in the flour and cook, stirring, for 1 minute. Gradually whisk in the milk. Increase the heat and bring to a boil, whisking often. Whisk in 3/4 cup parmesan cheese and remove from the heat.
Using a food processor fitted with a shredding disk, shred the baking potatoes and sweet potatoes separately. Place the baking potatoes in a large bowl, add cold water to cover and stir to rinse. Drain well and rinse again. Spread the baking potatoes in the prepared casserole dish. Spoon on half of the onion sauce, then top with the goat cheese and spinach. Top with the sweet potatoes and remaining sauce.
Grease a large sheet of foil with the remaining 1 tablespoon butter and place butter side down on top of the casserole dish; crimp around the edges to seal. Bake for 50 minutes. Remove the foil, sprinkle the remaining 1/2 cup parmesan on top and bake until golden, 15 to 20 minutes. Let cool for 15 minutes before serving.