01 - Preheat oven to 400°F. Lightly grease a 9x13-inch baking dish with olive oil and set aside.
02 - In a mixing bowl, combine the diced tomatoes, red onion, cilantro, minced jalapeño, garlic, lime juice, kosher salt, and black pepper. Stir gently until well incorporated, then set aside to allow the flavors to meld.
03 - Place the chicken breasts in the prepared baking dish. Sprinkle both sides of each breast evenly with ground cumin, chili powder, and paprika, pressing the spices gently into the meat.
04 - Spoon the prepared salsa fresca evenly over each seasoned chicken breast. Top generously with shredded Monterey Jack or mozzarella cheese, covering the surface of each piece.
05 - Bake uncovered for 25 to 30 minutes, or until the chicken registers an internal temperature of 165°F on a meat thermometer and the cheese is melted, golden, and bubbling.
06 - Remove from the oven and let the chicken rest for 5 minutes to allow the juices to redistribute. Garnish with additional fresh cilantro if desired, then serve immediately.