The only pastry where the dough is cooked twice — once on the stovetop, once in the oven. Flour is added to boiling water and butter, cooked until it forms a smooth ball that pulls away from the pan, then eggs are beaten in. In the oven, the high water content creates steam that inflates the pastry from inside, while the egg protein sets the structure. The result — éclairs, profiteroles, gougères, Paris-Brest — is simultaneously crisp, hollow, and light.
Water and butter brought to a rolling boil together — butter must be fully melted before the boil. All the flour added at once and stirred vigorously over heat for 2-3 minutes until the dough forms a smooth ball and a film forms on the bottom of the pan (this is the starch gelatinising). Cool slightly, then add eggs ONE AT A TIME, beating fully between each addition. The dough should be glossy and pipe smoothly — it falls from a spoon in a thick V-shape. Oven at 220°C for initial puff, then reduced to 180°C to dry out and set the structure.
The egg quantity varies by humidity and flour — add the last egg gradually, testing consistency. Pipe onto parchment, not greased trays. After baking, pierce the base with a skewer and return to a turned-off oven for 10 minutes to dry the interior completely. For gougères: fold in grated Gruyère before piping — the best cocktail snack ever invented. For croquembouche: each profiterole must be perfectly uniform, and the caramel assembly requires speed and confidence.
Adding flour before the water boils — uneven starch gelatinisation. Not cooking the panade (flour-water mixture) long enough — raw starch taste and weak structure. Adding all eggs at once — they won't incorporate. Dough too wet or too dry — it should hold a piped shape. Opening the oven during baking — steam escapes and choux collapses. Not piercing baked choux to release internal steam — they go soggy.