Preheat oven to 350 degrees. Spray a baking sheet with non-stick spray.
Place the chicken breasts on a cutting board and cut slits into the tops of the breasts, about 1/2 inch apart, being careful not to slice all the way through the chicken.
Transfer chicken to the baking sheet and drizzle olive oil over the chicken breasts.
Stir together the chili powder, cumin, paprika, garlic powder, and salt. Sprinkle over each side of the chicken.
Stuff a strip of onion and pepper inside each slit in the chicken.
Bake for 20-25 minutes or until chicken is just cooked through.
Squeeze the juice of the lime over each chicken breast. Divide the cheese between each breast and sprinkle over the top. Bake for 2 more minutes to melt the cheese.
Sprinkle with cilantro before serving
