Preheat oven to 430 °F (220 °C).

Prepare the basic choux pastry.

Fill a piping bag fitted with a star-shaped nozzle and pipe a round puff onto a baking sheet.

Bake briefly at 430 °F (220 °C) then lower heat to 350 °F (180 °C) and bake for about 20 minutes.

For the vanilla cream, warm the pastry cream.

Add water to the gelatin, remove excess water, and dissolve it in the pastry cream.

Flavor with Cointreau.

Beat in an ice water bath until cool and then fold in the whipped cream.

Let firm for 30 minutes in the refrigerator.

Halve the profiteroles horizontally, so that there are two even halves.

Pipe the vanilla cream onto the lower half with a piping bag fitted with a star-shaped nozzle and place the upper half back on top.

Dust with powdered sugar before serving.