Start by activating your yeast in lukewarm water (35°C) and leave for 15 minutes, until it foams.
Melt the butter in a small saucepan, then add the milk.
Place the flour, vanilla sugar and salt in the bowl of your food processor. Pulse gently, then add the yeast and finally the milk-butter mixture. Add the egg yolks.
Beat the egg whites until stiff, then fold in gently in 2 stages.
Leave the dough to rest, covered, at room temperature for at least 1 hour.
Preheat and lightly grease your waffle iron.
Pour a small ladleful into each mold.
Bake for 3-4 minutes until golden brown.
Serve waffles with powdered sugar, fruit coulis or caramel coulis.
