In medium saucepan melt butter and chocolate over low heat, stirring constantly. Remove from heat and cool. Blend in sugar and peanut butter. Beat in eggs one at a time.
Combine flour, baking powder and salt. Add to chocolate mixture along with vanilla. Beat till batter is smooth. Stir in nuts.
Pour into a greased 9x9x2" baking pan. Bake 350° 20-25 minutes
Cool on rack; cut into bars.
Makes 24Recipe submitted by Dobie on 2/22/01