1 lb. sustainable cod, red snapper, or tilapia, cut into 1/2-by-3-inch strips
2 to 3 limes, juiced
1 tsp. kosher salt
1 cup flour
2 tbsp. chili powder (I like Gebhardt) or chile de arbol powder
1 tbsp. dried oregano
1 ½ tsp. (1/2 palmful) ground cumin
Safflower, canola, or vegetable oil, for frying (about 6 cups for a Dutch oven or 2 qt. for a tabletop fryer)
1 small white onion, finely chopped
1 cup mixed fresh cilantro and flat-leaf parsley leaves, finely chopped
2 jalapeño chiles , finely chopped
About 1/4 cup Worcestershire sauce
2 tbsp. EVOO
6 tomatillos—husked, rinsed, and coarsely chopped
1 small or 1/2 medium onion, chopped
½ ripe Haas avocado
About 1/2 cup fresh cilantro leaves
About 2 tbsp. fresh mint leaves
2 serrano or jalapeño chiles, coarsely chopped
1 clove garlic, crushed
1 lime, juiced (about 2 tbsp.)
12 to 16 small corn tortillas, charred, or tostada shells
Chopped iceberg lettuce or thinly shredded green or white cabbage
Mexican crema or sour cream
For the fish, in a medium bowl, mix the fish with the juice of 1 lime (about 2 tbsp.) and the kosher salt.
In another medium bowl, whisk the flour and spices.
In a Dutch oven, large pot, or tabletop fryer, heat the safflower oil to 375°.
Working in a couple of batches, dredge the fish liberally in the flour and shake off any excess. Fry the fish until browned and cooked through, about 5 minutes per batch. Transfer the fish to a wire rack set over paper towels to drain.
Place the fish in a medium bowl and break it up a bit. Add the onion, herbs, chiles, Worcestershire, and EVOO. Toss gently until evenly incorporated. Add the remaining lime juice to taste; season with salt.
For the salsa, in a food processor or blender, puree the tomatillos; season with salt. Add the onion, avocado, cilantro, mint, chiles, garlic, and lime juice. Pulse until fairly smooth. Season the salsa with salt. Thin it with 1/4 to 1/2 cup water if it’s too thick.
Fill the tortillas with the fish, salsa, lettuce, crema, and avocado.