1 (15 ounce) can pumpkin pie filling
12 ounces evaporated milk
3 eggs
1 cup granulated sugar
4 teaspoons pumpkin pie spice
1 (18.25 ounce) box yellow cake mix
3/4 cup butter, melted
1 1/2 cups chopped walnuts

Preheat oven to 350 degrees F.

Combine pumpkin, milk, eggs, sugar and pumpkin spice. Mix well. Pour into greased 9 x 13-inch baking dish. Sprinkle dry cake mix over pumpkin mixture; drizzle on melted butter and sprinkle on walnuts. Bake 1 hour until knife inserted in the center comes out clean.