6 tablespoons butter, softened
1-1/3 cups sugar
3 tablespoons thawed lemonade concentrate
2 tablespoons grated lemon peel
2 teaspoons vanilla extract
2 eggs
2 egg whites
2 cups all-purpose flour
1 teaspoon baking powder
1/2 teaspoon baking soda
1/4 teaspoon salt
1-1/4 cups buttermilk
FROSTING:
1 package (8 ounces) reduced-fat cream cheese
2 tablespoons butter, softened
2 tablespoons grated lemon peel
2 teaspoons thawed lemonade concentrate
1 teaspoon vanilla extract
3-1/2 cups confectioners' sugar