Preheat the oven to 200 degrees Celsius (392 degrees Fahrenheit).
Pour water and butter into a pot and bring to a boil.
Add flour and vanilla sugar to the pot and stir together to make a dough (choux pastry).
Remove the pot from the heat and let it cool until you can touch it (approx. 5 min.).
Crack 1 egg into the pot and whisk it with the dough.
Crack another egg into the pot and whisk.
Crack the last egg into the pot and whisk.
Whisk until the dough comes together and looks shiny and smooth – it should be sticky.
Pour the dough into a piping bag or freezer bag and cut a 1.5-2 cm hole in it.
Pipe the dough onto a baking sheet in small sticks of 5-7 cm.
Bake them in the oven for about 30-35 min. – keep an eye on the color.
When they come out of the oven, make a hole in them to let the steam out.
Let them cool on a rack.
Fill them with pastry cream, whipped cream, or jam and decorate with icing or powdered sugar.