PREHEAT oven to 350° F. Grease 9 1/2-inch Bundt pan. Sprinkle nuts in bottom of prepared pan.
BEAT cake mix, 2 cups pumpkin pie mix, eggs and oil in large mixer bowl for 2 minutes. Spoon into prepared pan.
BAKE for 35 to 40 minutes or until wooden pick inserted in cake comes out clean. Cool in pan on wire rack for 15 minutes. Invert onto wire rack to cool completely. Transfer cake to serving platter.
COMBINE remaining pumpkin pie mix, brown sugar and evaporated milk in medium, heavy-duty saucepan. Bring mixture to a boil over medium heat. Boil for 1 minute; remove from heat. Serve warm sauce with slices of cake.