In a large mixing bowl, whisk together dry ingredients. In a separate bowl, beat eggs until light and pale yellow. Add eggs, pumpkin puree, and evaporated milk to the dry ingredients and mix well. Pour into a greased 9×9 baking dish. Set aside.
Cut the butter into small cubes. Place in a small bowl, and slowly add in the cake mix. Mix with a fork until the mix combines with the butter and becomes crumbly. Evenly pour the cake topping on the pumpkin pie.
Bake on 425°F for 15 minutes. Decrease the oven temperature to 350°F and bake for another 40-45 minutes, until a toothpick comes clean.
When the pumpkin pie cake finishes baking, let set for about 1-2 hours, then serve. Top with whipped cream and enjoy!