Sterilize a 1-quart jar in boiling water; set aside to drain. Scrub the lemons under hot water to remove any wax or dirt.
Cut into quarters leaving attached at the stem end. Gently spread the quarters apart and add 1 tablespoon salt.
Place in jar and repeat with remaining lemons, pressing down to pack.
Fill the jar with lemon juice to within 1/2-inch of top and tightly seal with lid.
Before using, place in a cool dark place for at least 3 weeks turning occasionally to evenly distribute the juice and salt.
Store jars in refrigerator for up to 6 months. To use, remove the pulp and rinse under cool water to remove salt. Refrigerate after using.