Combine the 2 chicken breasts, juice from 1 lime, the 1/2 cup chopped cilantro, the 2 cloves chopped garlic, the 1/2 teaspoon ground coriander, the 1/2 teaspoon pepper, the 1 teaspoon dried oregano, the 1 teaspoon salt, the 1 teaspoon cumin, and 2 tablespoons of the olive oil in a large bowl and toss to coat chicken breasts. Cover and refrigerate at least an hour or up to a day in advance.

30 minutes before grilling remove chicken from the refrigerator. Heat outdoor grill over medium-high heat. Clean and brush grates with oil. While grill is heating, toss the 1 large onion, and 2 bell peppers in the remaining tablespoon of olive oil and season well with salt and pepper.

Place the chicken and vegetables on the preheated grill, draining & discarding any excess marinade. Grill the chicken for 5-6 minutes per side, or until cooked through with beautifully charred grill marks. The vegetables may take a few minutes longer. Grill them until they are lightly charred and tender.

Let cool slightly, then cut into bite-sized pieces.

Heat oven to 450°F and arrange rack in upper third of oven. Line a baking sheet with parchment paper. Place a layer of chips on the bottom, top with half of the chicken and vegetables, half of the black beans and half of the cheese. Repeat the layering; chips, chicken, beans, and cheese.

Bake on the upper third rack until cheese is fully melted and just browning at the edges (8–10 minutes). Broil 30–60 seconds for extra bubbly spots.

Remove and top with remaining ingredients. Serve with dollops of sour cream and pickled onions, if desired.