Assemble ingredients before starting. Break the eggs into a liquid measuring cup or spouted pitcher. Preheat oven to 425 degrees. Line 2 baking sheets with silicone baking mats or parchment paper.
Place the water, butter and salt in a heavy saucepan over medium-high heat. Bring to a simmer. Add the flour all at once and stir with a wooden spoon until it forms a thick dough. Continue to cook while stirring for about 1 minute.
Dump the dough into the bowl of an electric mixer preferably fitted with a paddle attachment. Mix on low speed for 30 seconds to cool the dough slightly. Add the eggs, one at a time, mixing well after each addition. After all the eggs have been added continue to mix, increasing the speed to medium-high, until the dough is smooth, thick and shiny, about 2 or 3 minutes.
Pipe the dough onto the prepared baking sheets in mounds or logs or use an ice cream scoop to scoop out the batter, spacing about 1 inch apart. If piping, moisten a finger with water and res down the peaks so they don't burn.
Bake for 10 minutes, turn the oven temperature down to 350 and bake for another 30 - 35 minutes depending on the size, or until the dough has risen and is golden brown and the cream puff has a hollow sound when tapped on the bottom. Turn off the oven and leave the puffs in the oven for 20 minutes. Remove from the oven and pierce the side of each puff with a sharp knife to let the steam escape. Let cool.