1Preheat oven to 350 degrees. Spray a 9×13 pan.
Remove 1 cup of cake mix from the cake mix box and set aside in a small bowl for the topping. Then in a large bowl combine the remaining cake mix with 1 egg and a 1/2 cup melted butter. Mix well, and pat into bottom of pan. Set aside
In the same bowl used for the base, mix together the pumpkin, eggs, sweetened condensed milk, pumpkin pie spice, brown sugar and cinammon. Combine well and pour over base mix in pan.
With a fork, combine your reserved cup of cake mix with the nuts and softened butter. Crumble over pumpkin mix.
Bake in preheated oven for 40 to 50 minutes until golden brown. Let cool for at least 20-30 minutes then cut in squares and sprinkle with powdered sugar before serving.