01 - Set oven temperature to 390°F.
02 - Using a sharp knife, make deep cuts about ½ inch apart across each chicken breast, being careful not to slice all the way through the meat.
03 - Combine the shredded mozzarella cheese, baby spinach, chopped sun-dried tomatoes, and minced garlic in a mixing bowl.
04 - Gently press the filling mixture into each cut of the chicken breasts, distributing evenly.
05 - Place the stuffed chicken breasts in a baking dish. Drizzle with olive oil and sprinkle with Italian herbs, paprika, salt, and black pepper.
06 - Bake for 25–30 minutes until the chicken is fully cooked and the filling is golden and bubbly.
07 - Allow the chicken to rest for 5 minutes before serving to retain juices.