Modified from https://www.epicurious.com/recipes/member/views/french-cheese-puffs-50084951
You should have all the ingredients ready to go before you start. Don’t let the water and butter boil away while you grate the cheese. Second is to let the batter cool for a few minutes before adding the eggs so you don’t ‘cook’ them. Make sure when you stir in the eggs that you do it vigorously. 1. Preheat the oven to 425F (220C.) Line a baking sheet with parchment paper. 2. Heat the water, butter, salt, and chile in a saucepan until the butter is melted. 3. Dump in the flour all at once and stir vigorously until the mixture pulls away from the sides into a smooth ball. Remove from heat and let rest two minutes. 4. Add the eggs, one at a time, stirring quickly to make sure the eggs don’t ‘cook.’ The batter will first appear lumpy, but it will smooth out. 5. Add about 3/4s of the grated cheese and the chives, and stir until well-mixed. 6. Scrape the mixture into a pastry bag pipe the dough into mounds, evenly-spaced apart, making each about the size of a small cherry tomato. 7. Top each puff with a bit of the remaining cheese, then pop the baking sheet in the oven. 8. Bake for 10 minutes, then turn the oven down to 375F (190C) and bake for an additional 20 to 25 minutes, until they’re completely golden brown. Serving: The puffs are best served warm, and if making them in advance, you can simply pipe the gougères on baking sheets and cook right before your guests arrive, or reheat the baked cheese puffs in a low oven for 5-10 minutes before serving. A bit of troubleshooting: The problem folks have with pâte à choux is them being deflated. The usual causes are too much liquid (eggs), or underbaking. Make sure to use large eggs, not extra-large or jumbo. And bake the puffs until they’re completely browned up the sides so they don’t sink when cooling.