Preparation / Directions:
Preheat oven to 350 degrees. Combine sugar and butter in a bowl; beat at medium speed of a mixer until well-blended. Add banana, milk, sour cream, and egg whites; beat well, and set aside.
Combine flour, baking soda, and salt; stir well. Add dry ingredients to creamed mixture, beating until blended.
Spoon batter into 4 (5 x 2 1/2 inch) miniature loaf pans coated with cooking spray. Bake at 350 degrees for 45 minutes or until a wooden pick inserted in center comes out clean. Let cool in pans 10 minutes on a wire rack; remove from pans. Let cool completely on wire racks.
Note: To make one 9 inch loaf, spoon batter into a 9 x 5 inch loaf pan coated with cooking spray; bake at 350 for 1 hour and 10 minutes.