Make sure all ingredients are at room temperature.
Preheat the oven to 175 ° C.
Mix all ingredients in a bowl to a nice, smooth batter.
1 minute on low speed and then 6 minutes on high speed.
Let the batter turn on low speed for another minute for a very fine structure.
Line the baking tray with parchment paper.
Fill the decorating bag with the batter and cut 2 cm from the tip of the pastry bag.
Pipe discs on the baking tray about 4 cm, pipe them 6 cm apart.
Put the icing sugar in a sieve and sprinkle the entire top of the discs with icing sugar.
Bake the sponge cake for 15 to 20 minutes in the middle of the preheated oven.
When the sponge cake feels firm on the top, it is done.
After baking let it cool down on the baking tray.