boil the milk and butter in a saucepan.
Remove it from the fire, add the sifted flour with the baking powder and stir until obtaining a smooth, compact ball, then heat for a minute, stirring constantly.
Put the ball in a bowl still hot and add the vanillin, one egg at a time, stirring until the dough gleams and drops heavily from the ladle, forming long points.
Put the dough in a piping bag with a large toothed nozzle and create 8/10 cm long dough strips, not too close to each other, on the oven plate lined with non-stick paper.
Cook for about 20 minutes in the middle part of the preheated oven (electric and gas: 200°C, ventilated: 190°C) without ever opening the oven.
Meanwhile prepare the white cream, with a simple variation of traditional Chantilly Cream: put the cold cream in a bowl (also let this cool in the fridge beforehand) and whip it by using electric whips.
When the cream begins to take on consistency, add the vanillin and icing sugar a little at a time, mixing them until obtaining a puffy and foamy cream.
Take out the eclairs and once they have cooled, cut them lengthwise and, by using the piping bag, stuff them with the white cream and close them again.
Then sprinkle them with the icing sugar.
The eclairs must be kept in the fridge until ready to be eaten.