Make the choux pastry first. Method to hold the piping bag: Wrap the end of the piping bag around your thumb. Squeeze the bag with your hand to let the pastry out. Pipe the choux puffs in staggered rows on a slightly greased baking sheet. Squeeze the piping bag to create a small bun, then make a sharp, circular movement to stop. Using a fork, glaze each choux bun with egg wash. I recommend using a fork instead of a brush to avoid the egg wash dripping down, which would prevent the puffs from rising during baking. ...
Mixture of beaten egg yolks and water.
Refers to the operation consisting in shaping dough or pastry on a baking sheet or mould, particularly when piping choux pastry to create buns, using a plain or fluted piping bag.