Preheat oven to 350 degrees. For First Layer: Mix cake mix (reserve 1 cup), melted butter and 1 egg. Press into a greased 9x13 baking
For Second Layer: In a medium bowl, mix together pumpkin, milk, eggs, brown sugar, and spices until blended and smooth. Pour over first layer.
For Third Layer: Mix reserved cake mix, melted butter and sugar until crumbly. Spread evenly over pumpkin layer.
Bake for 35-40 minutes until golden brown. Serve with whipped cream. Store in refrigerator.