Sweet American Sponge Cake

Servings: 10 people
Cook Time: 35 minutes
Prep Time: 40 minutes

Ingredients:
American Sponge Cake:
6 large eggs, separated
1 cup (100 grams) sifted cake flour
1/4 tsp baking powder
1/4 tsp salt
1 cup (200 grams) granulated white sugar, divided
1 tsp pure vanilla extract
2 tbsp water
Zest of a lemon or orange (outer skin)
3/4 tsp cream of tartar

Directions:
1. American Sponge Cake: Preheat oven to 350 degrees F (180 degrees C) and place rack in center of oven. Have ready an ungreased two-piece 10 inch (25 cm) tube pan.

2. Separate the cold eggs, placing the yolks in one bowl and the whites in another bowl. Cover the bowls with plastic wrap and bring the eggs to room temperature (about 30 minutes).

3. Meanwhile sift or whisk the sifted flour with the baking powder and salt. Set aside.

4. Place the egg yolks and 2/3 cup (135 grams) of the sugar in the bowl of your electric mixer, fitted with the paddle attachment (or use a hand mixer). Beat on high speed until they are thick, fluffy and light colored (when you slowly raise the beater the batter will fall back into the bowl in a slow ribbon). Then beat in the vanilla extract, water, and lemon zest. Set aside while you beat the egg whites.

5. In a clean bowl, with the whisk attachment, whip the egg whites until foamy. Add the cream of tartar and continue beating until soft peaks form. Gradually add the 1/3 cup (65 grams) of sugar and continue beating until the egg whites are shiny and just form stiff peaks.

6. Next, sift the flour mixture over the beaten egg yolks (about one third of the flour mixture at a time) and gently but quickly fold (with a wire whisk or rubber spatula) the flour into the egg yolk batter. Then gently fold a little of the beaten egg whites into the batter to lighten it, and then add the rest of the whites, folding just until incorporated. (Do not over mix the batter or it will deflate.) Pour the batter into the tube pan, smoothing the top.

7. Bake in preheated oven for 28 - 35 minutes or until a toothpick inserted into the center of the cake comes out clean. Remove from oven and immediately invert the pan (turn upside down) and suspend it by placing the inner tube on the top of a flat topped glass or bowl. Allow the cake to cool completely before unmolding (about one hour). Run a flat metal spatula or sharp knife around the inside of the pan and then remove the center core of the pan. Run the spatula along the bottom and center core of the pan. Invert the cake onto a greased wire rack. The cake can be served plain with a dusting of powdered sugar or with fresh fruit and softly whipped cream. This cake can be covered and stored for a few days, or it can be frozen.

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