1. Preheat your oven to 400°F (200°C). In a saucepan, combine water, butter, and salt. Bring to a boil, then add the flour all at once. Stir until the mixture forms a ball. Let it cool for 5 minutes.

2. Beat in eggs one at a time, mixing until fully combined and dough is smooth and glossy.

3. Transfer dough to a piping bag fitted with a round tip. Pipe small, medium, and large rounds onto parchment-lined baking sheet, spacing them out.

4. Bake at 400°F for 15 minutes, then reduce to 350°F (175°C) and bake for another 15–20 minutes until golden and crisp. Let cool completely.

5. For the filling, heat heavy cream and pour over chopped white chocolate or whisk in matcha. Chill and whip until soft peaks form. You can also whip plain cream with food coloring for a simpler version.

6. Slice each puff horizontally. Pipe the filling onto bottom halves, stacking small on medium on large. Add a star cookie on top.

7. Dust with powdered sugar and serve immediately or chill to firm up the cream before serving.