INGREDIENTS

• 1/2 cup water
• 1/2 cup milk
• 1 stick (4 ounces) unsalted butter, cut into tablespoons
• Large pinch of coarse salt
• 1 cup all-purpose flour
• 4 large eggs
• 3 1/2 ounces shredded Gruyère cheese (1 cup), plus more for sprinkling
• Freshly ground pepper

Preheat the oven to 400 degrees. Line two baking sheets with parchment paper. In a medium saucepan, combine the water, milk, butter and salt and 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 pan, about 2 minutes.

Scrape the dough into a bowl; let cool for one minute. Beat the eggs into the dough, one at a time, beating thoroughly between each one. Be sure that each egg is fully incorporated into the batter before adding the next. Don’t worry if the batter separates and looks curdled at first. Just keep beating!  It will come together nicely.  Finally, add the cheese and a pinch of pepper.

Transfer the dough to a pastry bag fitted with a 1/2-inch round tip and pipe tablespoon-size mounds onto the baking sheets, two inches apart. Sprinkle with cheese and bake for 16-20 minutes, or until puffed and golden brown. Serve hot, or let cool and refrigerate or freeze.