Preheat oven to 350 degrees F. In a large bowl, combine margarine, sugar, flour, cocoa, baking powder, eggs, milk and 1-1/2 tsp. vanilla. Beat well. Stir in walnuts.
Spread in a greased 13" x 9" pan. Bake 40 minutes or until brownies begin to pull away from sides of the pan.
Just before brownies are done, in a saucepan, melt chips with condensed milk and remaining vanilla. Immediately spread over hot brownies. Cool and chill before cutting.
Suggested Handi-Foil Products:
20394 – Ultimates® Cook-n-Carry® Utility Pans w/Lids
22002 – Ultimates® Utility Pans