1 (18.25 ounce) package white cake mix
1 (3 ounce) package instant vanilla pudding mix
1 1/2 cups pumpkin puree
1 cup margarine
1/2 cup white sugar
4 eggs
1 teaspoon baking soda
1 teaspoon cream of tartar
1 teaspoon vanilla extract
1 (10 ounce) package non-fat milk chocolate cookie mix
1 (8 ounce) container frozen whipped topping
Preheat oven to 350 degrees F (175 degrees C). Grease and flour 2 (9 inch) round pans.
Place cake mix in a large bowl. Mix together the vanilla pudding mix and pumpkin. Beat in butter, sugar and egg and mix until smooth. Stir in margarine, milk, sprinkles and whipped topping. Pour batter into prepared pan.
Bake in the preheated oven for 45 minutes, or until a toothpick inserted into the center of the cake comes out clean. Allow to cool. Chill before cutting into 1/2 inch squares.