Put water, butter, sugar, and salt in a saucepan and place over high heat. When mixture boils (butter should completely melt at same time), remove pan from heat and stir in the flour with a wooden spoon. Place the pan back on heat and cook the paste to dry it out; a thin paste will form on the bottom of the pan & paste will begin to come away from the sides of the pan (takes about one minute). Pour the paste into the bowl of an electric mixer fitted with a paddle attachment and beat the mixture; it will release steam. Allow to cool several minutes.

Add the eggs, one at a time, allowing each to fully incorporate before adding the next. The paste has absorbed enough eggs when: the spatula lifted out of the bowl forms a ribbon connecting the spatula to the batter; if the batter still seems too thick, crack and whisk one additional egg into a separate bowl and add about half into the whipping mixture to achieve “ribbon” consistency. The dough should be shiny and smooth. At this point you can pipe the batter to bake or store in the refrigerator for up to 2 days with plastic wrap directly against the surface.

Fit a large (#6) plain tip into a large plastic piping bag. Fill the bag no more than halfway full with choux paste (it is much easier to pipe this way). For a medium sized puff, pipe mounds of choux approximately 1- ½ “in diameter and 1” high, onto a parchment lined sheet pan.

Preheat oven to 425°, convection setting if available. Make egg wash by whisking one egg with a pinch of sugar and salt. Brush lightly and evenly over the puffs. Place the sheet pan(s) of puffs into preheated oven, and bake at 425° for 10 minutes. Rotate the pans, close the oven door and turn the oven down to 325°. Bake the choux for 15-18 more minutes until well browned and baked through. Check the bottoms and cracks to make sure that they are thoroughly baked (no white spots). Cool completely before assembling profiteroles. Alternatively, at this stage the puffs can be frozen in a zip block bag for several weeks until ready to use.