Summer Means Salsa (Spicy Fermented Salsa, That Is)

This spicy salsa is what I like to call the Harvest Special. If you planned it right this summer — and started those first sets of seeds last fall, however early that may seem — everything that goes into this salsa can come straight from your garden right now, from the garlic to the tomatoes!

But why fermented salsa? Why not normal salsa like you’ve always made?

I’ve used this same recipe for non-fermented salsa and it’s fine. Great, actually. But fermentation pushes it over the line to fantastic. The same bacteria and yeasts that give kraut and kimchi their distinctive flavor also give this salsa a bright and tangy note. It’s lively on the tastebuds without being too sour or too salty.

Fermented salsa undergoes the same process of lacto-fermentation as sauerkraut. Simply by letting your salsa sit out for a few days, you’ll encourage all kinds of beneficial bacteria in the mix, creating a powerful probiotic that you can’t nearly get enough of (the jar I made was gone in two days!). And while many recipes for fermented salsa call for the addition of whey or starter culture, this one lets the existing bacteria (already found in all your vegetables) do the work. It may take a day or two longer to ferment, but the ease is worth the wait.

Spicy Fermented Salsa

Makes 1 quart

Ingredients

1 1/2 pounds tomatoes, diced
1/2 red onion, diced
1/2  to 1 jalapeño pepper, minced (since some jalapeños are hotter than others, I recommend a taste test before putting the whole thing in there)
1/2 serrano pepper, minced
5 cloves garlic, minced
1/2 cup chopped fresh cilantro
1/2 teaspoon ground cumin
1 teaspoon pickling salt or sea salt
Juice from 1 lime
Extra-virgin olive oil

Method

In a medium bowl, mix all the ingredients together (including the juices from your tomatoes), but do not add the olive oil yet.

Pour the salsa into a quart-sized jar and run a chopstick around the jar to release any trapped air bubbles.

Add a half-inch layer of olive oil on top. The olive oil serves two purposes here: one, it prevents the vegetables from rising above the water and growing mold on the surface, and two, it adds a richness to the salsa once you mix it in.

Loosely seal the jar with a lid and leave it out of direct sunlight for a few days. The warmer your room temperature is, the faster your salsa will ferment. You’ll start to see fizzies as the lactic acid bacteria flourish.

In my very warm kitchen this summer, it took four days to develop a bold, tangy flavor. You could leave it for up to a week for the tang to intensify; the longer you let it ferment, the longer the salsa will keep (not that it would ever last that long in this household!).

Once the salsa’s to your liking, refrigerate the jar. The olive oil will congeal in the cold temp, but is perfectly safe to eat. Just mix it in with a spoon before you use the salsa, or let the jar rest at room temp before serving.