Sift together flour, baking powder and salt; set aside. Cream together shrtening and sugar in bowl until light and fluffy, using electric mixer at medium speed. Beat in eggs, one at a time, blending well after each addition. Stir in mashed bananas. Add dry ingredients all at once, stirring just enough to moisten. Gently mix in chopped nuts. Spoon batter into greased 3-inch muffin-pan cups, filling 2/3rds full. Bake in 350 degree F. oven 20 minutes or until golden brown. Serve hot with homemade jam or jelly.