1Pat chicken dry and season both sides with kosher salt, black pepper, cumin, and chili powder. Brush lightly with vegetable oil.
2Heat your grill to medium-high. Grill chicken for 6–7 minutes per side until cooked through and charred. Let rest 5 minutes, then slice into strips.
3While chicken rests, brush onion halves and whole peppers with oil. Grill until charred and softened, about 8 minutes for peppers, 5 for onion. Slice the peppers into strips and chop the onion.
4Heat the canned black beans in a small skillet over medium heat with a pinch of salt and cumin. Warm through and drain excess liquid.
5In a small bowl, mix sour cream, minced garlic, juice of 1 lime, and half the fresh cilantro (chopped). Add a pinch of salt.
6Warm the flour tortillas on the grill for 30 seconds per side until pliable.
7Lay each tortilla flat. Spread a spoon of cilantro-lime crema down the center. Layer with rice, grilled chicken, grilled peppers and onion, black beans, and shredded cheddar cheese.
8Fold in the sides of each tortilla first, then roll tightly from bottom to top. Serve with lime wedges and extra cilantro on the side.