Where can I get chocolate sponge cake to make a gateau?
Make one. Chocolate Sponge Cake: Preheat oven to 350 degrees F (180 degrees C) and place the oven rack in the center of the oven. Butter, or spray with Pam, a 17 inch (43 cm) by 12 inch (30 cm) jelly roll pan. Line the pan with parchment paper and then butter and flour the paper (or spray with Baker’s Joy). Set aside. While the eggs are still cold, separate the eggs, placing the whites in one bowl and the yolks in another. Cover with plastic wrap and bring to room temperature before using (takes about 30 minutes). Meanwhile melt the chocolate in a stainless steel bowl set over a saucepan of simmering water. Set aside. In the bowl of your electric mixer (or with a hand mixer) place the egg yolks and 1/4 cup (50 grams) of sugar and beat until this mixture is light and fluffy (about five minutes). (When you slowly raise the beaters, the batter will fall back into the bowl in a slow ribbon.) Beat in the vanilla extract. Add the melted chocolate and beat only to combine. Set aside while you
