Mix the butter with the sugar, the vanilla sugar, the salt and the eggs until frothy. Mix the flour with the baking powder, sieve and gradually stir in. Stir in enough butter milk until a liquid dough is formed. Brush the waffle iron with the oil and heat. Put a small ladle each in the hot waffle iron and bake the waffles for 4 to 6 minutes until they are golden brown.
Makes about 12 waffles.
Tip: taste best fresh from the waffle iron, but slightly cooled. Also delicious with a spoon of stiff, ice-cold cream.