Gougères

Heat the oven to 425°F (220°C). Line a baking sheet with parchment paper.

Combine the water, butter, salt, and pepper in a medium saucepan over medium heat. Bring to a rolling boil.

Add the flour all at once and stir hard with a wooden spoon until the mixture comes together into a smooth dough and pulls away from the sides of the pan.

Keep the dough on the heat and cook, stirring constantly, for 2 minutes — this dries the dough so the eggs incorporate cleanly. The dough should look slightly glossy and leave a thin film on the bottom of the pan.

Transfer the dough to the bowl of a stand mixer (or a large mixing bowl if mixing by hand). Let it cool for 5 minutes — warm enough to relax, cool enough not to scramble the eggs.

Add the eggs one at a time, beating well after each addition. The dough will look slippery and broken at first — keep going. It comes together into a smooth, glossy, ribbon-stage paste.

Stir in the grated Gruyère, the 1/4 cup Parmesan, and the parsley until evenly distributed.

Using two spoons or a small cookie scoop, drop heaping tablespoon-sized mounds onto the prepared baking sheet, spacing them about 1.5 to 2 inches apart (they expand significantly).

Brush each puff lightly with the beaten egg, then sprinkle a pinch of the finishing Parmesan on top.

Bake at 425°F (220°C) for 10 minutes — the high heat puffs them up tall. Without opening the oven, lower the temperature to 375°F (190°C) and bake another 20 to 25 minutes, until deeply golden and hollow-sounding when tapped.

Cool on the baking sheet for 5 minutes (they finish setting as they cool), then transfer to a rack. Serve warm, the same day.