Heat oven to 350° F. Line muffin cups - 2 1/2-inches in diameter), with foil bake cups.
Stir together flour, 1/4 cup sugar, cocoa, baking soda, baking powder and salt in large bowl; set aside.
In medium bowl, stir together yogurt, banana, milk, oil and vanilla; set aside.
In small bowl, beat egg whites until foamy. Gradually add remaining 1/2 cup sugar, beating well after each addition until stiff peaks form.
Stir yogurt mixture into flour mixture until moistened; fold in one-third of egg white mixture. Gently fold in remaining egg white mixture.
Fill muffin cups 3/4 full with batter.
Bake 20 to 25 minutes or until wooden pick inserted in center comes out clean. Remove from pan to wire rack. Cool completely.
Drizzle White Glaze over tops of cupcakes. Let stand until set Store, covered, at room temperature.
Servings: 20 cupcakes