- ½ red onion, sliced thin
- Pinch black peppercorns
- 1 bay leaf
- ¾ cup white vinegar
- 1 teaspoon cumin seeds, toasted (see No-Nonsense Guacamole for instructions)
- ⅓ cup olive oil
- 1½ teaspoons chili powder
- ¼ cup chopped fresh cilantro leaves, plus more for garnish
- ½ to 1 jalapeno pepper, seeded and minced
- Kosher salt
- 1 pound flaky white fish (such as flounder, red snapper, or cod), cut into 4 pieces
- Freshly ground black pepper
- 8 fresh corn or flour tortillas
- Salsa Fresca and/or Savory Cabbage Slaw, for serving
- Sour cream, for serving
- 2 limes, quartered
For the Quick-Pickled Onions
In a small mason jar with a lid, arrange the onion slices, adding a pinch of peppercorns and a bay leaf, and pour in enough white vinegar to cover. Set aside to marinate for at least 30 minutes.
For the Tacos
Grind the toasted cumin into a coarse powder with a mortar and pestle. In a small bowl, mix the olive oil, chili powder, cumin, chopped cilantro, and jalapeno, and season with salt. Place the fillets on a baking sheet and pour the marinade over, making sure to coat the fillets well on both sides. Marinate for 20 minutes at room temperature.
Heat the broiler with the oven rack in the highest position. Season the fish with salt and pepper. Broil until the fillets are browned on top and the flesh is opaque throughout, about 5 minutes. Remove the pan from the oven and flake the fish with a fork. Taste and adjust seasoning as needed, then set aside. Lower the oven temperature to 400°. Place the tortillas in two stacks of 4, and wrap the bundles in aluminum foil. Heat in the oven for 7 to 10 minutes, until the tortillas are warmed through. Place the tortillas, still wrapped in foil, in a tea towel to keep warm.
To assemble the tacos, place a heaping spoonful of Savory Cabbage Slaw on the center of a tortilla. Add the flaked fish and Salsa Fresca, and top with the marinated onions. Serve accompanied by cilantro sprigs, sour cream, and lime wedges.
PRO TIP: You will most likely have leftover pickled onions. Keep them submerged in the vinegar in a refrigerated airtight container. You can then use the vinegar for other cooking, such as in salad dressings, and the pickled onions on anything from scrambled eggs to grilled chicken. Both will keep for several weeks.