Preheat oven to 400°F/190°C or 375°F for a convection oven.
In a medium saucepan add water and butter. Bring to a boil. Turn off the heat and pour in the flour. Mix to form a dough. Return to medium heat and stir continuously for 3 minutes. The dough should pull away from the sides of the pan and form a ball of dough.
Transfer the dough to a large bowl. Use a hand mixer on low, to mix the dough for 2 minutes to speed up cooling. Add the eggs one at a time, mixing well with each addition. Finish with a quick mix on high speed.
Use a pastry bag fitted with a star tip and pipe a disc of dough 3"-4" across, followed by an additional circle of dough on top to create a space for the custard, or simple mound the dough with a spoon. Make 8-10 mounds.
Bake for 25-30 minutes. Do not open the oven before 25 minutes or the cream puffs will collapse. After 25 minutes take a toothpick and pierce a hole to allow excess steam to escape and bake for an additional 5 minutes.
Remove the cream puffs from the oven and cool completely before filling.
Use a paring knife and cut the pastries in half. Pipe or spoon a ring of cooled pastry cream inside, cover with the top half. Add a dollop of pastry cream on top and a maraschino cherry. Dust with powdered sugar and serve.