1 c. all purpose flour
1/2 c. firmly packed brown sugar
1/2 c. butter, softened

TOPPING:

1 c. firmly packed brown sugar
2 tbsp. flour
1 tsp. baking powder
2 eggs
6 oz. pkg. chocolate chips
1/2 c. chopped nuts

Heat oven to 350 degrees. Lightly spoon flour into measuring cup; level off. In small bowl, combine all crust ingredients; blend well. Press into ungreased 13 x 9 inch pan. Bake at 350 degrees for 8-10 minutes. Cool slightly. In medium bowl, combine 1 cup brown sugar, 2 tablespoons flour, baking powder and eggs; blend well. Stir in chocolate chips and nuts; pour over crust. Increase oven temperature to 375 degrees and bake 15-20 minutes or until golden brown. Cool completely. Cut into 36 bars.