As usual I changed it up a bit. I have found that pumpkin tastes better with sweetened condensed milk rather than evaporated milk and sugar.
1 15 ounce can of pumpkin purée
1 can of sweetened condensed milk
4 tsp of pumpkin pie spice (or combination of ground cinnamon, clove, nutmeg, cardamom and ginger)
1/2 cup melted butter
1 box of white or yellow cake mix
Preheat oven to 350
In a large mixing bowl combine first four ingredients with a whisk. Prepare a 9 x 13 baking dish with cooking spray or butter and pour the mixture into the baking dish. Gently sprinkle the cake mix on top of the pumpkin. Pour melted butter over the top of the cake mix evenly. Put into preheated oven for 50 to 60 minutes. Should be set and top golden brown. Let cool slightly and serve with ice cream Yum.
(I have found the longer it bakes the pumpkin mixture gets set a little bit better and comes out of the pan much easier)
Let me know if you try it and I hope you enjoy it.