Sift together flour, baking powder and salt. Melt butter or margarine and chocolate in saucepan over low heat. Remove from heat and cool slightly. Blend in sugar and eggs, one at a time. Beat 1 minute each. Add chopped nuts and dry ingredients; mix well. Chill at least 1 hour. Shape in small balls (1 tablespoon dough). Roll in confectioners' sugar. Place on greased cookie sheet. Bake in 300 degree oven for 18 to 20 minutes. Makes 3 dozen.