Chocolate Upside Down Cake

1 chocolate cake mix
6 tablespoons of cocoa powder
1 1/2 cups of brown sugar
1/2 cup chopped pecans or walnuts
2 2/3 cups of hot water

Pour cake mixture into a 9 x 13 greased cake pan. Mix cocoa and brown sugar together, sprinkle over cake mix. Pour hot water on top of brown sugar mixture. Bake at 350 for 45 minutes. Serve warm with whipped cream.