In a 9 × 13 pan, mix the pumpkin puree, evaporated milk, 3 eggs, ¾ c sugar, ¼ c brown sugar, and 2 tsp pumpkin pie spice.
Sprinkle one box of yellow cake mix on top.
Pour one cup (2 sticks) melted butter all over the top. Do not mix it.
Bake at 350 for 50-60 mins.
