Preheat oven to 180ºC . grease pie plate 9x 3 cm. Beat eggs, margarine and chocolate till smooth, 10 seconds in blender on high or 30 seconds with hand beater. Add brown sugar, Bisquick and granulated sugar. Beat till smooth, 1 minute in blender on high (stopping occasionally to scrape down sides) or 2 minutes with hand beater. Pour into plate; sprinkle with nuts. Bake till knife inserted in centre comes out clean; about 35 minutes. Cool.