For the cake Preheat oven to 350°.
Line Muffin tin with muffin cups.
Lightly spoon sifted flour into dry measuring cups, and level with a knife. Combine sifted flour, baking powder, salt, and baking soda. Combine sugar, butter, and oil in a large bowl, and beat at medium speed of a mixer until well-blended (about 5 minutes). Add egg whites, 1 at a time, beating well after each addition. Combine the milk and yogurt. Add the flour mixture to the creamed mixture alternately with the milk mixture, beginning and ending with flour mixture. Stir in extracts.
Pour cake batter into cupcake pans with foil. Sharply tap cake pans once on countertop to remove air bubbles. Bake at 350° for 25 minutes or until a wooden pick inserted in center of cakes comes out clean. Cool in pans 10 minutes on wire racks, and remove from pans. Cool completely on wire racks.
For frosting Combine first 5 ingredients in top of a double boiler; place egg white mixture over barely simmering water in bottom of double boiler on cooktop. Beat at high speed of a hand-held mixer until stiff peaks form and candy thermometer registers 160°. Add extracts; beat until blended.