Preheat oven to 400°F. Gather all ingredients.
Heat 2 tablespoons of the oil in a large cast-iron skillet over medium-high. Rub chicken evenly with 3 tablespoons of the taco seasoning mix; set remaining 1 tablespoon taco seasoning mix aside. Add chicken to skillet; cook, flipping once, until browned on both sides, 3 to 4 minutes per side. Transfer to a plate (chicken will not be fully cooked). Do not wipe skillet clean.
Heat remaining 1 tablespoon oil in same skillet over medium. Add onion and chile; cook, stirring occasionally, until softened and slightly browned, about 4 minutes. Add corn; cook, stirring often, until slightly softened, about 2 minutes.
Stir in garlic, tomato paste, and reserved 1 tablespoon taco seasoning mix; cook, stirring constantly, until fragrant and tomato paste is darkened in color, about 2 minutes. Stir in black beans and tomatoes; remove from heat.
Place chicken in a single layer over vegetables in skillet; add any accumulated juices from plate. Bake in preheated oven until an instant-read thermometer inserted into thickest portion of chicken registers 155°F, about 15 minutes; let rest for 10 minutes. (Temperature will continue to rise to 165°F.)
Transfer chicken to a cutting board, and slice; return chicken to skillet.
Top with avocado slices.
Garnish with queso fresco and cilantro. Serve with lime wedges.
