About an hour before starting the cake, separate your egg whites from yolks. Cover the yolks with water and refrigerate for a later use. In measuring cup or small bowl let the egg whites warm to room temperature.

Preheat oven to 375° and set rack to middle shelf.

Sift flour and powdered sugar together and set aside.

Beat egg whites with cream of tartar in the bowl of a stand or hand mixer until foamy and cream of tartar has distributed evenly throughout whites.

Beat in sugar 2 tablespoons at a time, on high speed, until stiff and glossy. Add the extracts and salt with the last addition of sugar.

Remove bowl from stand mixer and sprinkle flour-sugar mixture, ¼ cup at a time, over the meringue, folding it just until the flour-sugar mixture disappears.

Push batter into an ungreased tube pan, 10x4 inches. Cut gently through batter with a metal spatula or gently tap on counter to settle batter.

Bake until cracks feel dry and top springs back when touched lightly, 30 to 40 minutes. I removed mine when a tester inserted into one of the cracks came out with only a few clinging crumbs.

Invert pan on bottle and cool completely.

To remove cake from pan, gently insert a flat offset spatula against the sides and carefully cut all the way around. You can use a small thin knife or a cake tester to cut around the middle tube. Gently flip cake over on a cooling rack, remove the pan and place the cake right side up with your hands. It should feel as light as air!