1 1/4 cups egg whites, at room temperature (about 9 large eggs)
1/4 teaspoon salt
1 teaspoon cream of tartar
1 teaspoon lemon extract
1 teaspoon vanilla extract
1 1/2 cups sugar
1 cup bleached cake flour, sifted (measure and then, sift)

For the glaze:
1 cup confectioners sugar, sifted
2-3 tablespoons fresh lemon juice
1 tablespoon finely grated lemon zest

Preheat oven to 325 degrees F. 

Beat egg whites until frothy; add salt, cream of tartar and lemon oil and vanilla extract. Continue beating until they form stiff but not dry peaks. Using a rubber spatula, gradually fold in the sugar, 1/4 cup at a time. Using the same rubber spatula, gradually fold in the flour, 1/3 at a time. Be sure that you use a true folding motion, gently turning the spatula from the bottom of the bowl to the top, folding in air with each stroke as opposed to beating or stirring. 

Pour batter into an ungreased, 9-inch angel food cake pan. Bake one hour or until top is golden brown. Remove cake from oven . 

Cool in the pan ten minutes and then invert pan and let cake stand upside down for an hour or until cooled.

While cake is cooling prepare the glaze. In a small bowl, whisk together confectioners sugar, lemon juice and lemon zest. Let stand ten minutes before glazing the cake as it thickens a little. 

Serve immediately.