Serves:  12-14 cupcakes                                 
Fat grams: 2.3
Phase:  4                                                         
Protein:  4.5

Ingredients:

2 tablespoons fat-free margarine, softened
3/4 cup sugar substitute
1 egg
1 egg white
1/2 cup plus 2 tablespoons 1% buttermilk
1/3 cup water
1 tablespoon white vinegar
1 teaspoon vanilla extract
1-1/2 cups flour
1/4 cup baking cocoa
1 teaspoon baking soda
1/2 teaspoon light salt
1/3cup miniature chocolate chips

In a mixing bowl, cream butter and sugar. Add egg and egg white, one at a time, beating well after each addition. Beat on high speed until light and fluffy. Stir in buttermilk, water, vinegar and vanilla. Combine the flour, cocoa, baking soda and salt; add to batter just until moistened. Stir in chocolate chips.
Fill muffin cups coated with nonstick cooking spray three-fourths full. Bake at 375 degrees for 15-18 minutes before removing from pans to wire racks.