Preheat oven to 355°F. Line baking sheet with parchment paper. Spray with baking spray and lightly dust with flour. Set aside
In a large bowl, add eggs and sugar. Beat on high speed for 10-12 minutes or until the mixture has tripled in size.
In a small bowl, combine cocoa, flour and baking powder. Gently fold the flour mixture into the egg mixture with a spatula. (Beat with a mixing spoon on low speed for a few seconds, just to make sure flour is well incorporated. Don't overbeat or mixture will flatten.)
Pour batter into the baking sheet. Bake 12-14 minutes.
Once baked, let cool about a minute. With a sharp knife, release edges of cake from baking sheet.
Roll cake into a roulade. Set aside to completely cool.