Mix the flour, milk, the eggs and the pinch of salt in a mixing bowl. Make sure the mixing bowl is big enough. Now beat the mixture with a hand mixer until fluffy. The dough is ready when it is smooth but throws small bubbles.
Put the bowl in the fridge and let the dough rest for 20 minutes.
After the resting time, take the dough out of the refrigerator and add the mineral water and sugar. Stir again until it is well mixed.
Now place the pan with plenty of butter (about a big tablespoonful per pancake) on the hot stove and let it melt. Be sure to heat the pan only over medium heat, otherwise the butter can burn easily.
Now take the pan off the heat and swirl it so that the butter spreads everywhere. Now take a ladle (soup ladle) full of batter and slide it into the pan. Swirl the pan again so that the pancake batter spreads everywhere and put it back on the flame.
Bake the first side until you can easily lift it with the spatula on the edge of the pan and it is golden brown. The first side is done when the top dough is already slightly firm and not so runny.
Now you can slide the spatula under the pancake and flip it. Do this carefully so that the pancake does not break. Then put some butter back into the pan and fry the other pancake(s) (or pancakes).
When you have finished all the pancakes, drape them on a plate. Sprinkle the top with the vanilla sugar.Now you can roll up the pancakes or simply fold them over and serve. There are no limits to your creativity.