1 pkg. (2 layer size) yellow cake mix
1 pkg. (4 serving size) vanilla instant pudding and filling
4 eggs
1 c. water
1/4 c. oil
1 c. crunchy peanut butter

Combine ingredients in a large bowl and mix on medium speed for 4 minutes. Pour into greased and floured bundt pan and bake 50 to 60 minutes. Cake should spring back when lightly pressed. Cool in pan 15 minutes and remove from pan.