Season both sides of the chicken breasts with taco seasoning.
Heat 1 tablespoon of oil in a large skillet over high heat. Add the chicken breasts and cook for about 4-5 minutes per side until browned and mostly cooked through. Remove from the pan, cover, and keep warm.
Reduce the heat to medium and add the remaining oil to the skillet. Add the chopped onion and cook for about 5 minutes until soft. Add the minced garlic and cook for another minute until fragrant.
Stir in the black beans, corn kernels, diced tomatoes, and diced green chiles. Cook for about 5 minutes, stirring occasionally.
Return the cooked chicken breasts to the skillet, nestling them into the black bean mixture. Simmer for 6-7 minutes until the chicken is fully cooked through (internal temperature reaches 165°F).
Once the chicken is cooked through, sprinkle the shredded Mexican cheese blend over the top. Cover the skillet with a lid and cook for a few minutes until the cheese is melted.
To serve, garnish with fresh cilantro if desired. Enjoy this delicious Santa Fe Chicken with rice, tortillas, or your favorite side dish.