Pre heat oven 350 degrees. Lightly grease or spray a 9x13 pan.
In a bowl stir together the pumpkin, sugar and eggs. Mix in the evaporated milk and pumpkin pie spice; pour into the prepared pan.
Sprinkle DRY cake mix over the pumpkin then drizzle melted butter over the cake mix
Bake for 1 hour-or until a knife inserted into the cake comes out clean.