In another bowl, beat the egg yolks with the remaining sugar very well. You can use a hand mixer or whisk by hand, but make sure they are well beaten.

Gradually fold the beaten egg whites into the yolks in several additions, using gentle folding motions to keep the mixture light and airy.

Sift the flour together with the baking powder. Add it to the mixture in two parts, folding gently each time to fully incorporate it into the batter.

Preheat the oven to 350°F (180°C), top and bottom heat. Bake for about 10 minutes, as the thin layer cooks quickly.

Once baked, let it cool slightly (do not let it cool completely) and remove the parchment paper. Trim the edges with a knife to make a perfect rectangle. Place the cake layer on a clean kitchen towel, roll it up with the towel to shape it, and let it cool completely.

Spread a layer of pastry cream on top, sprinkle with a little sugar, and caramelize it with a kitchen torch or hot iron.

As always, I recommend watching the video for a better understanding.