Whip the egg yolks, whole eggs, and 85g of sugar with a hand mixer.
Beat 25g of sugar with the egg whites to stiff peaks. Fold into first mixture.
Mix in the flour and cocoa.
Weigh 360g of batter on a 30 x 40 cm baking sheet and spread out with an angled spatula.
Bake at 446°F (230°C) in a convection oven for about 6 to 7 minutes.