I am not typically a fan of sweet potatoes at the holidays, but I have had some great ones lately. This is one of the recipes I have had. I made these on Thanksgiving for the Stauffer Family Thanksgiving. I will say they took longer to cook than the recipe said. Next time I make it I might boil the potatoes for a short while before making the casserole. I'll let you know how that works. Now, I will say even though they took longer to make- they were amazing! If you are going to make it for a smaller family (not a holiday meal) I would cut everything in half.
3 T butter
3 large onions, thinly sliced
6 large sweet potatoes, very thinly slices (about 14 cups)
2 cups of shredded Asiago cheese
1 teaspoon of salt
2 cups of heavy whipping cream
In a large skillet, melt butter over medium heat. Add onions; cover, and cook, stirring occasionally, for 20 minutes, or until onions are very tender. Uncover, increase heat to medium-high and cook for 5 or 6 minutes, starring frequently, or until onions are caramel colored. Remove from heat, and set aside.
Preheat oven to 350 degrees. Spray a 13 x 9-inch baking dish with non-stick cooking spray.
Layer potato slices over bottom of baking dish to cover. Sprinkle evenly with 2 tablespoons cheese, 1/4 teaspoon salt, and 2 tablespoons of cream. Pour remaining 1 1/2 cups cream over top of layers. Sprinkle evenly with 1 1/2 cups of cheese and top with caramelized onions. Cover with aluminum foil, and bake for 1 hour to 1 hour and 10 minutes, or until potatoes are tender. Let stand for 10 minutes before serving.