Place flour and sugar in the bowl of a food processor, and process for a few seconds to combine. Add butter, and process until the mixture resembles coarse meal, about 10 seconds. With the machine running, add the ice water through the feed tube in a slow, steady stream, then egg yolks, processing just until the dough holds together. Do not process for more than 30 seconds.
Turn the dough out onto a work surface. Place on a sheet of plastic wrap. Flatten, and form into a disc. Wrap, and refrigerate at least 1 hour before using.