Step 1

Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch pan.

Step 2

Reserve 1 cup of cake mix from the package. In a bowl, combine remaining cake mix, 1 egg and melted margarine. Press mixture into the bottom and up the sides of a 9x13 inch pan to form a crust.

Step 3

Mix together the pumpkin, 3 eggs, sugar, cinnamon and evaporated milk until blended. Pour over the crust. Combine the brown sugar and reserved 1 cup cake mix, then cut in the margarine until mixture is crumbly. Sprinkle over the filling.

Step 4

Bake in the preheated oven for 50 minutes. Keep refrigerated.