Preheat your grill to high heat (450-500°F). Brush the ears of corn lightly with olive oil and place directly on the grill grates. Grill, turning occasionally, for 10-12 minutes until the kernels are charred in spots and deeply golden. Remove and let cool for 5 minutes.

Cut the kernels off the cob and transfer to a medium bowl. Add the diced jalapeño, red onion, fresh cilantro, lime juice, olive oil, salt, and chili powder. Toss well to combine. Taste and adjust salt and lime juice as needed. Set aside to let the flavors meld while you prepare the fish.

In a small bowl, combine the smoked paprika, cumin, cayenne, garlic powder, onion powder, salt, and black pepper to make the spice rub.

Pat the mahi-mahi fillets completely dry with paper towels. This is important for achieving a proper crust. Brush both sides generously with olive oil, then coat both sides evenly with the spice rub, pressing it gently to adhere.

Make sure the grill grates are clean and well-heated. Place the fillets on the grill and cook undisturbed for 3-4 minutes until the fish releases naturally from the grates and a crust has formed. Flip carefully with a wide spatula and cook for another 2-3 minutes until the fish is opaque and flakes easily with a fork. Internal temperature should reach 145°F.

Transfer the fish to a clean plate and use a fork to break it into large, rustic chunks — don't shred it too finely, you want satisfying pieces in each taco.

Warm the corn tortillas directly over the grill grates or over a gas flame for 20-30 seconds per side until soft, pliable, and slightly charred in spots. Keep warm wrapped in a clean kitchen towel.

To assemble, place 2 tortillas per serving on a plate. Top each tortilla with a generous spoonful of the spicy corn salsa, followed by chunks of the grilled spiced fish. Add avocado slices and a drizzle of sour cream or crema if desired.

Garnish with fresh cilantro sprigs and serve immediately with lime wedges and hot sauce on the side.