Pumpkin Pie Cake

"Yellow cake mix takes the place of crust in this pumpkin dessert reminiscent of a pumpkin pie in a dish."
INGREDIENTS:

1 (29 ounce) can pumpkin pie mix
1 cup sugar
1 can evaporated milk
4 eggs
1 tsp vanilla
1/2 t. salt
Topping:
1 yellow cake mix
1 cup butter, chilled
1 cup chopped walnuts or pecans (optional)
DIRECTIONS:
1. Preheat oven to 350 degrees F (175 degrees C) and lightly grease a 9x13 inch baking dish.
2.In a large bowl combine pumpkin,sugar, milk, 4 eggs,salt and vanilla. mix well and pour this mixture in baking dish.
3.In a medium bowl with a pastry blender, or in a food processor, combine chilled butter with cake mix until mixture resembles coarse crumbs. Sprinkle over pumpkin mixture. Sprinkle chopped nuts over all.
4.Bake for 1 hour, until top is golden. Cool and serve with cool whip or whipped cream.