This is actually very much like a sponge cake, though it has no flour whatsoever. It’s just the type of nifty and versatile invention Rose Levy Beranbaum is famous for. Yes it has some steps, but if you’ve made spongecake before it’ll be second nature. Start by preheating your oven to 375 degrees Fahrenheit. Then prepare your pan. Using two sheets of parchment lay one down on a sheet pan sprayed with cooking spray, but let several inches hang over the edge. Spray the top.
Lay on the other sheet, likewise leaving some to hang over the side. Spray everything.
Now for the chocolate. Break it up and place it in a microwave-safe bowl.
Zap it in the microwave for ten seconds on high, then stir. Repeat four or five times until it looks about like this:
Then stir, letting the residual heat melt the chocolate the rest of the way.
STOP! Don’t eat any of it.
Now combine the yolks and half the sugar in the bowl of a mixer.
Whip about five minutes on high until thick ribbons form.
Add the melted chocolate.
Stir the two together until they’re incorporated. Scrape the mixture into a large bowl and set it aside.
Wash the whip and bowl so you can make the meringue. Don’t get all freaky with the washing thing. Despite what you’ve heard, a couple of little flecks of a fatty mixture won’t ruin the foam. Not remotely.
Whip for about 30 seconds until the mixture is foamy, then add the creme of tartar.
Keep whipping another 2-3 minutes until the mixture is at soft peaks. Begin adding the remaining 1/4 cup sugar.
Whip to stiff peaks or thereabouts. Ooh…artsy!
Stir one third of the meringue into the chocolate mixture. Yes I said stir, round and round with your implement at this angle. This will lighten the mixture so the rest of the meringue can be folded in.
Now fold in the second third…
And the third third. Makes sure to leave a few small streaks.
Scrape the mixture into your prepared pan and smooth it out. Get a little obsessive here so the layer is nice and even. .
Bake about 15 minutes until the cake springs back when you touch it in the center.
Cool it on a rack for 5 minutes, then loosen the edges with a butter knife.
Dust the top with cocoa powder.
Put on a sheet of parchment.
Then an upside-down rack.
Remove the pan and gently peel back the first sheet of parchment from the inside of the sheet outward.
Now the other piece.
Dust the cake layer with more cocoa…
…lay on more parchment and let the cake cool completely. Freeze the cake until you’re ready to use it.