Heat oven to 325°. Grease 9x5x3-inch loaf pan. Mix flour, baking soda and salt. Beat shortening, butter, sugar and vanilla in large bowl with electric mixer until pale and fluffy. Beat in eggs one at a time until well blended. On low speed add dry ingredients alternately with buttermilk, then the mashed bananas. Turn into prepared pan. Bake 1 hour and 10 minutes or until pick inserted in center comes out clean. Cool in pan on rack 10 minutes. Unmold on rack; cool completely. Makes 1 loaf, 18 slices. Per slice: 152 cal, 2 g pro, 23 g car, 6 g fat, 36 mg chol with butter, 28 mg chol with margarine, 119 mg sod. bake 32