The cabbage served with pupusas is called curtido, a tangy, lightly pickled slaw that acts as the essential counterpoint to the rich, cheesy flatbread. It’s made from finely shredded green cabbage, carrots, onion, oregano, and vinegar, and the whole thing comes together in about 15 minutes of active work. The magic happens while it sits.
What You Need
Curtido uses a short list of everyday ingredients. For a batch that will last through several meals:
- Half a medium green cabbage (about 1.5 pounds or 8 cups shredded)
- 2 medium carrots, grated
- Half a red or white onion, thinly sliced
- 1 jalapeño, sliced into thin rings (optional, but traditional)
- Half a cup of white vinegar or apple cider vinegar
- Half a teaspoon of dried oregano
- Salt to taste
Red onion adds a nice pop of color, but white onion works fine. For the oregano, Mexican oregano is the authentic choice. It has a brighter, more citrusy flavor with peppery undertones compared to the Mediterranean variety you probably have in your spice rack. If you can find it at a Latin grocery store, use it. Regular oregano still tastes good here.
One note on vinegar: if you plan to make a longer-fermented version, use a brine of 1 cup vinegar to 1.5 cups water with 2 teaspoons of kosher or sea salt. Avoid iodized table salt, which can cloud the brine and affect the flavor.
How to Shred the Cabbage
Cut your cabbage half in half again, then slice out the dense core. Lay each quarter flat-side down and cut it into the thinnest shreds you can manage. You’re aiming for strips about the width of a matchstick. A sharp chef’s knife works best, though a mandoline speeds things up if you have one. The finer the shred, the faster the cabbage absorbs vinegar and the better it drapes over a pupusa.
Grate the carrots on the large holes of a box grater. They should be roughly the same thickness as the cabbage so everything pickles at the same rate.
The Blanching Step
This is where curtido differs from ordinary coleslaw. Before you mix anything, you soften the raw cabbage just enough to take the tough, squeaky edge off while keeping it crunchy. Place the shredded cabbage in a large colander or fine mesh strainer set in the sink. Bring a full kettle of water to a boil and pour it slowly, evenly over the cabbage. Then immediately rinse it with cold water to stop the cooking. Press down firmly with your hands or the back of a spoon to squeeze out as much water as possible.
This quick blanch wilts the cabbage just slightly so it can absorb the vinegar mixture. Skip it and your curtido will taste raw and stiff. Overdo it (like actually boiling the cabbage in a pot) and you’ll end up with limp, soggy slaw.
Mixing and Pickling
Toss the drained cabbage into a large bowl with the grated carrots, sliced onion, and jalapeño. Sprinkle the oregano and a generous pinch of salt over everything and toss to combine. Pour the vinegar over the top and mix thoroughly with your hands or tongs, making sure every layer gets coated.
Pack the mixture into a glass jar or airtight container, pressing it down so the liquid rises above the vegetables. If the vinegar doesn’t quite cover everything, that’s normal for the quick version. The cabbage will release its own water over the next few hours and the level will rise.
How Long to Let It Sit
This is where you have options, and the version you choose depends on when you need it.
For a quick curtido, cover the jar and refrigerate it for at least 1 to 2 hours. The cabbage will be lightly tangy and still quite crunchy. This is the weeknight version, and it’s perfectly good.
For a more traditional, deeper flavor, leave the jar at room temperature for 3 to 5 days. The natural bacteria on the cabbage will begin fermenting, producing a funkier, more complex tang similar to sauerkraut. After that counter time, move it to the fridge. Some people ferment their curtido for several weeks at room temperature, which creates a very sour, probiotic-rich result. That’s more of a personal preference than a requirement.
A fermented batch keeps in the refrigerator for one to two months. The vinegar-only quick version is best used within a week or two, because the vinegar flavor intensifies over time and can become overpowering.
Serving It Right
Pile the curtido generously on top of each pupusa. You want enough that every bite has some crunch and acid cutting through the melted cheese or beans inside. The slaw isn’t a garnish; it’s a full partner to the pupusa.
Traditionally, the other thing on the plate is salsa roja, a simple cooked tomato sauce. To make it, blend a can of whole tomatoes with half a white onion, a clove of garlic, a jalapeño or serrano pepper, two teaspoons of dried oregano, and salt. Simmer the blended mixture in a tablespoon or two of olive oil for about 10 minutes until it thickens slightly. A handful of fresh cilantro blended in at the end is common but optional. The sauce should be mild and smooth, not spicy. It plays the warm, savory role while the curtido brings the cold, acidic crunch.
Tips for Better Curtido
Taste the cabbage after blanching and before adding vinegar. If it still tastes like raw cabbage with no give at all, you may not have used enough boiling water. It should feel pliable but not soft.
Salt draws moisture out of the vegetables, which is what creates the brine. If your curtido looks dry after an hour in the fridge, you probably need more salt. Add half a teaspoon, toss, and check again in 30 minutes.
The jalapeño is traditional but truly optional. Many Salvadoran households skip it, especially when kids are eating. If you include it, remove the seeds for mild heat or leave them in for more kick. You can also substitute a few pinches of red pepper flakes for a subtler warmth distributed throughout the slaw.