Marbled-Chocolate Banana Bread

2 cups all-purpose flour
3/4 teaspoon baking soda
1/2 teaspoon salt
1 cup sugar
1/4 cup butter, softened
1 1/2 cups mashed ripe banana (about 3 bananas)
1/2 cup egg substitute
1/3 cup plain low-fat yogurt
1/2 cup semisweet chocolate chips

Preheat oven to 350°.

Lightly spoon flour into dry measuring cups, and level with a knife. Combine the flour, baking soda, and salt, stirring with a whisk.

Place sugar and butter in a large bowl; beat with a mixer at medium speed until well blended (about 1 minute). Add banana, egg substitute, and yogurt; beat until blended. Add flour mixture; beat at low speed just until moist.

Place chocolate chips in a medium microwave-safe bowl, and microwave at HIGH 1 minute or until almost melted, stirring until smooth. Cool slightly. Add 1 cup batter to chocolate, stirring until well combined. Spoon chocolate batter alternately with plain batter into an 8 1/2 x 4 1/2-inch loaf pan coated with cooking spray. Swirl batters together using a knife. Bake at 350° for 1 hour or until a wooden pick inserted in center comes out clean. Or Spoon batter as described into 12 muffin tins and bake for 18 minutes or until done. Cool 10 minutes in pan on a wire rack; remove from pan. Cool completely on wire rack.