Preheat the oven to 400°F (200°C).

In a medium saucepan, combine water and butter over medium heat until the butter melts.

Once melted, add flour and salt all at once, stirring vigorously until the mixture pulls away from sides of the pan.

Remove from heat and let the dough cool for about 5 minutes.

Add eggs one at a time, mixing well after each addition.

Line a baking sheet with parchment paper.

Transfer the dough to a piping bag and pipe small mounds 2 inches apart on the prepared sheet.

Bake in the preheated oven for 25 minutes or until puffed and golden brown.

Let the puffs cool completely before filling them.