PREHEAT oven to 350°F. Mix flour, wafer crumbs, baking powder and salt; set aside. Beat margarine and sugar in medium bowl with electric mixer on medium speed until creamy. Add eggs; beat until light and fluffy. Blend in bananas. Add flour mixture alternately with milk, beating well after each addition. Stir in 1/2 cup of the walnuts.
POUR into greased 9x5-inch loaf pan. Sprinkle with remaining 1/4 cup walnuts.
BAKE 1 hour 10 min. or until wooden toothpick inserted in centre comes out clean. Cool in pan 10 min.; remove to wire rack. Cool completely.
serving size = 1 slice (80 g)