01 -
Preheat oven to 350°F (175°C). Lightly spray a 9×13-inch baking dish with cooking spray.
02 -
Cook spaghetti according to package directions until al dente. Drain and set aside.
03 -
In a large mixing bowl, combine cooked chicken, cream of chicken soup, sour cream, drained spinach, 1 cup of Monterey Jack cheese, minced garlic, and half a can of French Fried Onions.
04 -
Add cooked spaghetti to the chicken mixture and stir until well combined. Pour into prepared baking dish.
05 -
Sprinkle remaining 1 cup of Monterey Jack cheese over the pasta. Evenly spread the remaining French Fried Onions on top.
06 -
Bake uncovered for 40-50 minutes, until casserole is hot, bubbly, and onions are golden brown.