Gather the ingredients.
Preheat the oven to 400°F. Line two baking sheets with parchment paper. In a medium saucepan, combine the water, milk, butter, and salt; bring to a boil.
Add the flour and stir it in with a wooden spoon until a smooth dough forms; stir over low heat until it dries out and pulls away from the side of the pan, about 2 minutes.
Scrape the dough into a bowl; let cool for 1 minute. Beat the eggs into the dough, one at a time, beating thoroughly between each one. Add the cheese and a pinch each of pepper and nutmeg.
Transfer the dough to a pastry bag fitted with a ½-inch round tip and pipe tablespoon-size mounds onto the baking sheets, 2 inches apart. Sprinkle with cheese and bake for 22 minutes, or until puffed and golden brown.
Serve hot, or let cool and refrigerate or freeze. Reheat in a 350°F oven until piping hot.
