Pat the fish fillets dry with paper towels. Season both sides with 1 tsp kosher salt and 1 tsp freshly ground black pepper. Drizzle or brush with 1 tablespoon lime juice and let rest 10 minutes while you prepare other components.

Blackened option

If choosing blackened: mix all Blackening Seasoning ingredients in a small bowl. Rub seasoning evenly over both sides of the fillets. Heat a large cast-iron or heavy skillet over medium-high heat until very hot and add 1 to 2 tablespoons vegetable oil. Sear the fillets 2–3 minutes per side (depending on thickness) until a dark crust forms and fish flakes easily (internal temp ~145°F / 63°C). Transfer to a plate and keep warm, loosely tented with foil.

Crispy option

If choosing crispy: whisk the flour, cornstarch, 1/2 tsp salt and 1/4 tsp pepper in a bowl. Add cold sparkling water (or beer) and stir to make a smooth, slightly thick batter. Heat 1/2 cup vegetable oil in a skillet over medium-high heat to about 350°F (use a thermometer) or hot enough that a drop of batter sizzles and floats. Cut fish into taco-sized pieces, dip each piece into the batter to coat, then carefully lay into hot oil. Fry in batches 2–3 minutes per side until golden and crisp. Transfer to a wire rack or paper towels to drain and sprinkle a pinch of salt.

Pico de Gallo

Combine diced tomatoes, diced onion, chopped cilantro, minced jalapeño (if using), 1 tablespoon lime juice and 1/2 teaspoon salt in a bowl. Stir and taste; adjust lime or salt as needed. Let rest 10–15 minutes at room temperature to allow flavors to meld.

Spicy Mayo

Whisk together 1/2 cup mayonnaise, 1 tablespoon sriracha, 1 teaspoon lime juice and 1/2 teaspoon extra hot sauce or chili oil if using. Taste and adjust heat or acidity. Transfer to a squeeze bottle or small bowl.

Assembly & Serving

Warm the corn tortillas: heat a dry skillet over medium-high heat and warm each tortilla 20–30 seconds per side until pliable and lightly charred in spots; keep warm wrapped in a clean towel.

Arrange shredded cabbage on each warmed tortilla. Place a piece or portion of cooked fish on top of the cabbage.

Spoon pico de gallo over the fish, add sliced or diced avocado, and drizzle with spicy mayo. Garnish with extra cilantro leaves and a squeeze of lime. Sprinkle a tiny pinch of salt over the avocado if desired.

Serve immediately with lime wedges on the side. Provide choice of blackened or crispy fish when plating.