Add water and sea salt to your saucepan and heat until salt is dissolved. Set aside to cool.

Wash your tomatoes thoroughly.

Pack your glass jar as full as you can without crushing the tomatoes. It’s best to leave the tomatoes whole.

If using fresh herbs, add basil, mustard seeds, or garlic cloves into the jar with the tomatoes for extra flavor.

Once the saltwater brine has cooled, pour it over the tomatoes, and make sure that they are fully covered in the brine.

Set a fermenting weight on top of the tomatoes to keep them below the brine. I use a pickle pebble but you can simply use a rock in a ziplock bag!

Add a loose lid or fermentation lid to the top of the jar. Put the jar on a plate or towel to catch any overflow and leave it sit in a room temperature place. I like to simply leave mine on our kitchen countertop!

How long the fermentation process will take depends on the temperature in your home. A small batch in half-gallon mason jars can be ready in 6-8 days, while a gallon jar may take 3-4 weeks. You will know fermentation is happening when bubbles form in the salt brine, and it becomes foggy due to carbon dioxide release and lactic acid formation.

After the tomatoes are fermented (this will either take a week or a month depending on the size of your jar), move the fermented tomatoes to cold storage, such as the fridge or a cool, dark place, to slow down further fermentation.