To make the tacos:
In a small bowl, combine the ancho powder, cumin, garlic, salt, and pepper and stir to mix. Add the oil and whisk until a loose paste is formed. Rub the fish with the spice paste and let marinate in the refrigerator for at least 30 minutes and up to 4 hours.
Light a charcoal fire or preheat your gas grill on high. Oil the grill’s cooking surface. Let the coals burn down to a medium-hot fire or adjust the gas grill burners to medium-high.
Grill the fish until just cooked through, 3 to 4 minutes per side. Transfer to a cutting board and coarsely chop.
Divide the tortillas into 2 stacks and wrap each in aluminum foil. Place on the grill until heated through, about 5 minutes.
In a large bowl, combine the green and red cabbage.
To assemble the tacos, take 2 tortillas, top it with chunks of fish, a dollop of the sauce, a spoonful of the Pico de Gallo, and some of the cabbage. Squeeze a wedge of lime over the filling, fold the tortillas, and eat.
Meredith Deeds grew up in San Diego and taught me the ins and outs of the fish taco. These are an adaptation of her mom’s recipe.