01 -
Preheat your oven to 500°F. Lightly coat a 13x9-inch baking dish with cooking spray and set it aside.
02 -
In a bowl, mix together the mayonnaise, sour cream, parmesan cheese, black pepper, and garlic salt to form the sauce.
03 -
Evenly spread fresh spinach on the bottom of the prepared baking dish. Layer uncooked chicken breasts over the spinach, then spread the creamy sauce over the chicken.
04 -
Sprinkle shredded Monterey Jack cheese on top. Place the baking dish on the bottom rack of the oven and bake for 20 to 25 minutes, or until spinach wilts and chicken is fully cooked.