1/2 cup butter or margarine, softened
2/3 cup brown sugar
2 egg yolks
1 teaspoon vanilla extract
1 1/2 cups all-purpose flour
1/2 teaspoon baking powder
1/2 teaspoon salt
1/4 teaspoon baking soda
3 cups miniature marshmallows

Topping
2/3 cup corn syrup
1/4 cup butter or margarine
1 package peanut butter chips
2 teaspoons vanilla extract
2 cups Rice Krispies cereal
1 cup salted peanuts
1 cup plain M&M's

Cream together butter and brown sugar. Beat in egg yolks and vanilla. Combine dry ingredients. Gradually add to creamed mixture until mixture resembles coarse crumbs. Press into a greased 9 x 13-inch pan. Bake at 350 degrees F for 12 to 14 minutes. Sprinkle with marshmallows and bake 2 to 3 minutes longer. Cool.

For topping, combine corn syrup, butter and chips in a saucepan over medium heat until all has melted and smooth. Remove from heat and stir in vanilla extract, cereal, peanuts, Rice Krispies and M&M's. Spread over crust. Cool completely before cutting.