01 - Set a grill pan or large skillet over medium-high heat and allow it to come to temperature.
02 - Coat the chicken breasts evenly with olive oil, garlic powder, smoked paprika, salt, and black pepper. Place on the hot grill pan and cook for 6 to 7 minutes per side until the internal temperature reaches 165°F. Transfer to a plate and rest for 5 minutes before slicing thinly against the grain.
03 - In a mixing bowl, combine the mozzarella, cheddar, Parmesan, minced garlic, mayonnaise, and fresh parsley. Stir until all ingredients are evenly incorporated into a cohesive spread.
04 - Lay each tortilla flat on a work surface. Divide the cheese mixture evenly among the four tortillas, spreading it across the center. Layer with spinach, tomato slices, red onion if using, and the sliced chicken.
05 - Fold in the left and right sides of each tortilla toward the center, then roll tightly from the bottom up to form a secure wrap.
06 - Wipe the skillet clean and return it to medium heat. Place the wraps seam-side down and grill for 2 to 3 minutes per side until the exterior is golden brown and the cheese has fully melted.
07 - Slice each wrap in half on a diagonal and serve warm.