Chocolate Peanut Butter Delights

3/4 cup butter
1-1/2 cups sugar
3 eggs
1 tsp vanilla extract
1-1/3 cups all purpose flour
3 tbsp baking cocoa
1/2 tsp baking powder
1/2 tsp salt
4 cups miniature marshmallows

Topping:
1-1/3 cup chocolate chips
1 cup peanut butter
3 tbsp butter
2 cups crisp rice cereal

In a mixing bowl, cream butter and sugar. Add eggs and vanilla; beat until fluffy. Combine flour, cocoa, baking powder and salt; add to creamed mixture. Spread in a greased 15 x 10 x 1" pan. (I used a 13x9" pan)

Bake at 350 for 15-18 minutes. Sprinkle marshmallows evenly over cake; return to oven for 2-3 minutes. Using a knife dipped in water, spread the melted marshmallows evenly over cake. Cool. (I did not have to spread the marshmallow layer because I used a 13x9" pan, so the 4 cups of marshmallows amounted to an even, single layer of marshmallows)

For topping, combine chocolate chips, peanut butter and butter in a small saucepan. Cook over low heat, stirring constantly, until melted and well blended. Remove from heat; stir in cereal. Immediately spread over bars. Chill.