Butterscotch Brownies

2 C all-purpose flour
2 tsp baking powder
1/4 tsp salt
1/2 C butter or margarine
2 C packed brown sugar
2 eggs
1 tsp vanilla extract
1 C chopped nuts
confectioners' sugar

Preheat oven to 350. Grease 9x13" baking pan. Sift together flour, baking powder, and salt in medium bowl. Melt butter in pan over medium heat; remove from heat. Add brown sugar; mix until well blended. Add eggs; mix well. Stir in vanilla. Add flour mixture to saucepan; mix well. Stir in nuts. Pour into prepared baking pan, spreading evenly. Bake 30 minutes or until cake pulls away from side of pan. Cool in pan 10 minutes. Cut into squares while still warm. Dust with confectioners' sugar.