Sprinkle a clean work surface with flour. Form the dough into a disk, then use the heels of your hands to push down in the middle and stretch the dough away from you.
Fold the far end over itself, toward you, forming a half circle, and press down firmly.
Rotate the dough counterclockwise by a quarter turn. Repeat the stretching, folding, and turning, dusting with flour if the dough sticks.
Once the dough is smooth (no visible lumps) and elastic (it doesn’t break when you stretch it thin)—after about 10 minutes of kneading—poke it with your finger. The indentation should fill in quickly. It’s hard to over-knead, so if you’re unsure, give the dough a few more turns.