Sterilize Your Jar: Submerge a 1-quart wide-mouth jar in boiling water for 1 minute.
Using tongs, carefully lift it out, pouring the water back into the pot.
Place it upside down on a clean towel to drain and cool. 2. Prep the Lemons: Scrub the lemons well and pat them dry. From the top (bud end), slice each lemon into quarters lengthwise, stopping about 1/2 inch from the bottom so the lemon remains connected at the base. 3. Salt the Lemons: Gently open the lemon quarters and generously pack the insides with sea salt. 4. Pack the Jar: Place a tablespoon of salt at the bottom of your sterilized jar. Tightly pack the salt-filled lemons inside, pressing down firmly to release their juices and fit as many as possible. 5. Submerge and Seal: Pour enough additional fresh lemon juice into the jar to completely cover the lemons.
Sprinkle another tablespoon of salt over the top. Seal the jar tightly. 6. Ferment: Let the jar sit in the refrigerator for at least 3 weeks, shaking it gently every few days to redistribute the salt and juices. The lemons are ready when the rinds are soft and translucent.