Fold in the flour and salt, mixing until a shaggy dough forms. Knead the dough on a floured surface until it’s smooth and elastic, about 8-10 minutes. If it’s sticking like crazy, sprinkle a bit more flour, but don’t go overboard. Let the dough rest in a covered, oiled bowl in a warm place. You want it to double in size, which should take about an hour.