6 egg whites, 6 egg yolks, 90 grams of sugar, 120 grams of flour, 6 grams of white wine vinegar
With the help of a planetary or electric mixer, whip the egg yolks with half the sugar. Once you get a frothy mixture, set it aside. With the help of the same planetary or whisk, whip the egg whites, incorporating the sugar and white wine vinegar a little at a time. When the egg whites are stiff, add them to the yolks with a gentle movement from bottom to top, so that they do not come apart. Sift the flour and gently add it to the mixture. Pour the mixture into a sac-à-poche and make the biscuits directly on a baking sheet lined with parchment paper. Sprinkle with granulated sugar. Bake in pre-heated oven at 200 degrees for 15-20 minutes.