Twice Baked Potato Casserole

Name: Twice Baked Potato Casserole
Ingredients: 10 large russet baking potatoes (about 7 pounds total); 8 tablespoons (1 stick) plus 1 tablespoon unsalted butter, at room temperature; 1 cup sour cream; 1/2 cup heavy cream; 2 teaspoons salt; 1 1/2 teaspoons freshly ground black pepper; 3/4 pound bacon, cooked until crisp and crumbled; 1/2 pound sharp white Cheddar, cut into 1/2-inch cubes; 3/4 pound mild Cheddar, grated (3 cups); 1/2 cup finely chopped green onions; 3 eggs, lightly beaten