for serving: plum jam (traditional topping) or apple puree or roasted apples, fruit sauce, etc.
optionally
2 tablespoons of raisins soaked in rum or other alcohol
cinnamon
Preparation
Warm the eggs (e.g., in warm water). Soak the raisins (if using) in alcohol or hot water.
In a bowl, add flour, mix with milk with a whisk to a uniform mass. Add egg yolks (save the whites) and vanilla sugar and mix again. Finally add drained raisins.
Beat the egg whites separately with a small pinch of salt until stiff peaks form. Add to the yolk mixture and gently mix with a spoon without deflating the beaten whites.
Heat a pan with butter. When the butter starts to sizzle, clarify it (remove the foam). Spread the butter over the entire pan surface, pour the mixture for the omelet, level the surface.
Fry over low heat for about 5 minutes or until the omelet is nicely browned on the bottom. Then flip it to the other side with a large spatula - the omelet may tear, as in the next step we tear it into smaller pieces with, for example, two forks. Flip the omelet pieces and fry from the other sides (not too long, until the raw batter sets).
Transfer to a plate, sprinkle with powdered sugar and optionally cinnamon. Serve with plum jam or apple puree.