Preheat the oven to 400ºF.
Place the chicken breasts on a cutting board, and with a sharp knife, butterfly each chicken breast open, then cut to create 4 thinner pieces of chicken.
In a small bowl, combine the salt, smoked paprika, cumin, garlic powder, and pepper.
Sprinkle half of the seasoning mix on the tops of the chicken breasts, then flip over and season the second side with the remaining seasoning.
Heat the olive oil in a large oven-safe skillet (I like to use cast iron) over high heat. When the oil is shimmering, add the chicken to the skillet. Cook for 1 ½ minutes, then flip over and cook on the second side for another 1 ½ minutes. Turn off the heat and pour the salsa verde evenly over the pieces of chicken. Transfer the skillet to the preheated oven, and cook until the chicken is cooked through, 8-10 minutes. During the last minute of cook time, add one slice of cheese to the top of each piece of chicken.
Sprinkle the fresh cilantro over the finished chicken.
Serve over rice with slices of avocado, if desired.
