1 1/2 sticks butter
2 c. sugar
1 1/2 c. flour
1/2 c. Nestle cocoa
1/2 tsp. baking powder
1/4 tsp. salt
4 eggs
2 tsp. vanilla
1 (12 oz.) pkg. chocolate chips
1/2 c. nuts, chopped (optional)

Preheat oven to 350 degrees. Melt butter. Remove from heat. Add sugar, flour, cocoa, baking powder, salt, eggs and vanilla. Stir until well blended and smooth. Stir in 1 1/2 cups chocolate chips and nuts. Spread in a greased 9 x 13 inch pan. Sprinkle with remaining 1/2 cup chocolate chips. Bake 30 to 35 minutes until set. Cool on wire rack. Cut into squares.