Butter an 8-inch springform pan and preheat oven to 375 degrees F.
In a large mixing bowl, place 2 1/2 cups squash flesh, 1 cup bread crumbs, eggs, grated cheese, mascarpone, nutmeg, salt and pepper, and stir to blend well. The resulting mixture will have a batter-like consistency. Use the remaining bread crumbs to dust the springform pan. Pour the batter into the pan and bake until set and a toothpick exits cleanly, about 30 45 minutes. Remove the pan from the oven and let it cool 20 minutes. Unmold on to plate and serve either hot or cold.
Recipe courtesy of Mario Batali