01 - Preheat oven to 400°F (200°C).
02 - In a mixing bowl, combine diced tomatoes, red onion, cilantro, jalapeño, garlic, lime juice, salt, and black pepper. Stir gently to incorporate all ingredients and set aside to allow flavors to meld.
03 - Lightly coat a 9x13-inch baking dish with olive oil to prevent sticking.
04 - Arrange chicken breasts in the prepared baking dish. Season both sides evenly with ground cumin, chili powder, and paprika, pressing the spices gently into the meat.
05 - Spoon the prepared salsa fresca evenly over each chicken breast, covering the surface completely.
06 - Generously sprinkle shredded Monterey Jack or mozzarella cheese over each salsa-topped chicken breast.
07 - Bake uncovered for 25–30 minutes, until the chicken reaches an internal temperature of 165°F (74°C) and the cheese is golden and bubbly.
08 - Remove from the oven and let rest for 5 minutes before serving. Garnish with additional fresh cilantro if desired.