Preheat and Prep the Fish

1. Preheat your oven to 375°F (190°C).
2. Line a large baking sheet with parchment paper or a silicone liner for easy cleanup.
3. In a small bowl, mix together: ½ tsp cumin, ½ tsp cayenne, 1 tsp salt, ¼ tsp black pepper.

2. Season and Bake the Fish

1. Lay your tilapia fillets on the prepared baking sheet.
2. Evenly sprinkle the spice mixture over both sides of the fish.
3. Lightly drizzle with olive oil, and dot each fillet with small bits of unsalted butter.

3. Bake & Optional Broil

1. Bake the fish for 20‑25 minutes in the preheated oven.
2. If you want browned, crisp edges, switch to broil for the final 3‑5 minutes, watching carefully so nothing burns.

4. Make the Sauce

1. In a medium bowl, combine sour cream, mayonnaise, fresh lime juice, garlic powder, and Sriracha.
2. Whisk until smooth and well blended. Taste and adjust Sriracha or lime as needed.

5. Prep Toppings & Tortillas

1. While the fish is baking, shred the purple cabbage, slice the avocados, dice tomatoes (if using), chop red onion, and remove cilantro stems.
2. Grate Cotija cheese.
3. Warm tortillas by toasting them quickly on a large dry skillet or griddle over medium‑high heat until soft‑tortilla floppy and lightly charred in places.

6. Assemble the Tacos

1. Flake or cut the cooked fish into pieces.
2. Place a few pieces of fish on a warmed tortilla.
3. Add cabbage, sliced avocado, tomato, red onion, and cilantro.
4. Sprinkle cheese over those toppings.
5. Drizzle the sauce generously over everything.
6. Serve immediately with lime wedges to squeeze over the tacos.