1 - Turn on your oven, 400 F ° In a bowl, combine flour, salt and yeast.
2 - Melt the butter with water in a saucepan and bring to boil.
Once the mixture boils, remove from heat and pour at once mixing flour-salt-yeast.
Mix with a wooden spoon until the dough forms a ball and no longer sticks to the sides of the pan.
3 - Add the sugar and vanilla sugar. Mix.
4 - Add a first egg and mix until completely incorporated into the dough.
Repeat this process for the two remaining eggs.