CRUST:

1 1/2 c. all-purpose flour
2/3 c. firmly packed brown sugar
1/2 tsp. baking powder
1/2 tsp. salt (optional)
1/4 tsp. baking soda
1/2 c. softened butter
1 tsp. vanilla
2 egg yolks
3 c. miniature marshmallows

TOPPING:

2/3 c. corn syrup
1/4 c. butter
2 tsp. vanilla
1 (12 oz.) bag peanut butter chips
2 c. salted peanuts (without skins)
2 c. Rice Krispies cereal

Heat oven to 350 degrees. Combine all crust ingredients EXCEPT marshmallows. Press in bottom of ungreased 9x13 inch pan. Bake 12-15 minutes until light brown. Immediately sprinkle marshmallows over crust and return to oven for 2 minutes until slightly melted. Remove from oven.

In a large saucepan, heat corn syrup, butter, and peanut butter chips just until chips are melted and mixture is smooth. Remove from heat and mix in cereal and nuts. Spread over crust and marshmallows evenly. Refrigerate to cool. Cut into 1-inch squares.