Wash your tomatoes and herbs.
Mix the salt and water together and pour into your jar.
Add the garlic and herbs to the jar.
Pack in your tomatoes as tightly as possible so that you can’t possibly fit in one more (without breaking the tomatoes, or course), leaving an approximately 1-inch headspace at the top of the jar. You want to ensure the tomatoes are completely submerged under the brine.
Top with a quart-sized ziplock bag. I gleaned this trick from the book, Fermented Vegetables. Simply press the plastic down onto the top of the ferment and then fill the bag with water and seal. The bag will act as both a follower and weight. No need to buy any fancy equipment. Then screw on the lid (but not too tightly) in order to let some of the fermentation gasses escape.
Set aside out of direct sunlight at room temperature (60-70°F is preferred) for 3 weeks. You may want to set this ferment on a plate to catch any brine overflow as the tomatoes ferment. Check every couple of days to ensure the tomatoes remains submerged. Soon you’ll see bubbles of carbon dioxide gas in the brine, which means you’ve been successful and the brine has started to acidify. This is the stage in which you will begin to “burp” your jar every couple of days if you are using a standard sealing lid. Simply unscrew the lid slightly and allow the gas to escape. Then retighten the jar lid.
Once the tomatoes are finished fermenting, remove the plastic bag, tighten the lid, and store in the fridge or other cold storage. They will keep refrigerated for up to a year.