Grilled Salmon Tacos with Avocado Crema

 Special equipment: a grill basket

1. For the salmon: Whisk the lime zest and juice, brown sugar, olive oil, chilli-lime seasoning, 1 1/2 teaspoons salt and several grinds of black pepper together in a small bowl until well combined. Pour into a 9-by-13-inch rimmed baking sheet. Place the salmon flesh-side down on top of the marinade and refrigerate for at least 30 minutes and up to 1 hour.
2. Meanwhile, for the avocado crema: Place the avocado, sour cream, lime zest and juice, coriander, 1 teaspoon salt and several grinds of black pepper in a food processor and process until very smooth. Taste and adjust the seasoning with more salt and pepper if needed. Cover and refrigerate until ready to serve.
3. For the peppers and onions: Toss the pepper, onion, olive oil, 1 teaspoon salt and several grinds of black pepper together in a medium bowl until coated. Set aside until ready to grill.
4. Once the salmon has marinated, preheat a grill to medium-high direct-heat cooking for 15 minutes. Remove the salmon from the marinade and place skin-side down on a clean, dry surface, wiping any excess moisture or marinade from the skin.
5. For grilling and serving: Brush the grill grates clean. Oil the grates very well by soaking a small rag or paper towel in canola oil and then rubbing it over the grates with tongs. Carefully place the salmon skin-side down on the grill (take care to keep the skin dry; pat it dry if necessary).
6. Grill the salmon until the skin releases from the grates easily and the salmon is turning opaque around the edges, about 10 minutes.
7. Using tongs, lift a corner of the fillet and carefully slide a large metal spatula under the skin, lifting with the tongs as you go. Flip the salmon in one decisive motion and let cook until it reaches the desired doneness, about 2 minutes more for medium-rare. Transfer the salmon to a platter, sprinkle with more chilli-lime seasoning and let rest for 5 minutes.
8. Meanwhile, place a grill basket on the grill and add the peppers and onions. Cook, stirring occasionally with tongs, until the veggies are tender and nicely charred, 4 to 5 minutes. Transfer to a serving bowl.
9. Place the tortillas on the grill and cook, flipping once, until lightly charred, 1 to 2 minutes.
10. To serve, flake the salmon into large chunks. Top the tortillas with the grilled peppers and onions, the flaked salmon, a drizzle of avocado crema, crumbled Cotija and coriander leaves. Sprinkle with more chilli-lime seasoning and serve.