Wearing gloves, slice each pepper into thin, even slices. The more seeds you leave, the spicier your jalapeños will be. If you want to tone down the heat, you can remove some or all of the seeds.

Pack sliced jalapeños into a wide mouth pint jar.

In a small saucepan over medium heat, dissolve 1 tbsp of sea salt in 1 pint of water. Let cool slightly before pouring over the jarred jalapeños. It's okay if the water is still a little warm, just make sure it isn't so hot it can cook the peppers.

Screw on a plastic lid or fermentation lid. If you use a regular lid, you will need to "burp" the jar once every 24 hours.

Let the ferment sit on the counter, away from direct sunlight, for 3-5 days. Taste the jalapeños after day 3 and evaluate if they've fermented long enough. After that point it's really up to you and how sour or "pickled" you like them.

Once they're done to your liking, move them to the fridge. They can be stored under refrigeration safely for at least 6-12 months.