So then, after mixing the choux is ready to go. Preheat your oven to 425 degrees. Spoon the choux into the pastry bag of your choice, fitting it was a collar but no tip (so as to maximize choux outflow). Pipe it into the shape of your choice. Here I’m making short, stubby éclairs, which I prefer over the foot-longs you sometimes see. You can pipe onto a silpat or parchment paper, whichever you have around (if you’re using parchment make sure to stick the paper down to the sheet pan by planting a small dab of batter under each corner).
I do a wavy, zig-zaggy pattern which isn’t the way Jacques Pépin would have me do it, but he wasn’t here to help, so…
Make sure when you’re piping that you pile the choux up some as opposed to just spreading it out. I sort of angle my bag at a steep angle so my little puddles have some height to them. This ensures that the finished product is nice and tall instead of simply wide. Next give them a spritz with water (the extra steam helps the rise).
Bake for 10 minutes, then turn the oven down to 375 and bake for 10-15 minutes more, until golden.
But we’re not done yet. They need to dry out, and the best way to get that process started is by releasing the steam that’s trapped inside. Do that by poking slits in the bottom of the shells with a good sharp knife.
Leaving them upside-down, the final step is to put them back in the turned-off oven for several hours. Since the oven will still be quite hot at this point, you’ll need to prop the oven door open with something for the first ten minutes or so to release the heat. Say, a wooden spoon. When the ten minutes have elapsed, remove the spoon and close the oven door, leaving them for two hours or even overnight if you wish.