In a pot, over medium heat, melt the butter with water and salt.

When it starts to boil, add all the flour and mix well until a ball forms.

Remove the pot from the heat and let it cool slightly.

Add one egg at a time, making sure they are fully incorporated with a spatula before adding the next one.

When you have added all the eggs, prepare a baking sheet with baking paper.

Then proceed to put all the pastry in a piping bag fitted with a smooth tip.

Start piping some 3cm rounds on some parchment paper, leaving enough space between each ball.

Bake the choux pastry at 200C for 15 minutes, then drop the temperature to 190C and bake for a further 10 minutes, or until the buns are golden.

Set aside and let the buns cool down completely before filling.

For the filling, prepare your favourite creme patissiere and let it cool completely in a bowl covered with cling film, so that it's touching the whole surface and no skin will form on top of it.

Once cold, transfer the creme patissiere to a piping bag fitted with a smooth tip, big enough to let the creme patissiere flow through. 

With a knife, poke a hole at the bottom of each bigne, then fill each one with the creme patissiere until they feel nice and plump. Careful not to overdo it with the cream, they might explode in your hand!

Set each filled bigne aside on a serving dish and fill all of the bigne.

Complete with a dusting of icing sugar to serve.