Prepare the Chicken: First, slice chicken breasts in half lengthwise to create 4 smaller cutlets, rinse and pat dry then set aside. In a small bowl, mix together garlic powder, chili powder, smoked paprika, salt, and pepper then season all sides of the chicken breasts ensuring they are well coated with the spices.
Brown the Chicken: In a large skillet, heat the olive oil over medium heat. Add the seasoned chicken breasts and cook for about 5 - 7 minutes on each side, or until they are nicely browned and cooked through. Once done, remove the chicken from the skillet and set it aside on a plate.
Cook the Onion: In the same skillet, add the chopped onion. Sauté for a few minutes until the onion is soft and translucent. Add Tomatoes, Beans, and Corn: To the skillet, add the can of Ro-tel tomatoes and green chilies, drained and rinsed black beans, and drained corn. Stir to combine all the ingredients.
Simmer: Reduce the heat to medium-low and let the mixture simmer for about 5 minutes, allowing the flavors to meld together.
Return Chicken to Skillet: Place the cooked chicken breasts back into the skillet, on top of the vegetable and bean mixture, spooning some of the mixture on top of the chicken breasts. Let everything heat together for a few more minutes.
Add Cheese: Sprinkle the Mexican cheese blend over the chicken. Cover the skillet with a lid or aluminum foil and let it sit for a few minutes until the cheese is fully melted.
Garnish and Serve: If desired, garnish with fresh chopped cilantro before serving.