Galette de Pérouges

Preparation

1. Step 1

   Combine the yeast, flour, salt, 1 tablespoon sugar, cold butter, egg, and lemon zest in a food processor. Turn the machine on, let it run for a second until the mixture is blended, then let the machine run while you add 1/4 cup water through the feed tube, a little at a time, until the mixture forms a ball and is slightly sticky to the touch. If dry, add another tablespoon or two of water and process for another 10 seconds. (In the unlikely event that the mixture is too sticky, add flour, a tablespoon at a time.)

   Step 2

   Turn the dough onto a very lightly floured work surface and knead by hand for a few seconds to form a smooth, round dough ball. Place in a bowl, cover with plastic wrap or a damp cloth, and let rise in a warm, draft-free spot until the dough just about doubles in size, or at least 1 hour. (You can also let the dough rise more slowly, in the refrigerator, for as long as 6 or 8 hours.)

   Step 3

   Preheat the oven to at least 500°F (600°F is better if your oven goes that high) with a pizza stone in place if you have one. Knead the dough lightly and place it on a very lightly floured surface; sprinkle it with a little more flour and cover with plastic wrap or a towel. Let it rest while the oven heats.

   Step 4

   Pat or roll out the dough as thinly as possible to a diameter of 12 inches, using a little more flour if necessary. The process will be easier if you allow the dough to rest occasionally between rollings. If you have a pizza stone in your oven, place the dough on a floured peel or a long-handled board; if you do not, lay the dough on a lightly buttered baking sheet.

   Step 5

   Spread the dough with the softened butter and sprinkle it with the remaining sugar. Bake until the crust is nicely crisp and the sugar lightly caramelizes, about 10 minutes; if the galette is browning unevenly, rotate it back to front about halfway through cooking time. Serve hot or at room temperature, but within the hour.