Preheat oven to 350 degrees Fahrenheit. Spray 9x13" cooking dish with nonstick spray.
Cook egg noodles according to package directions. Drain and return to pan. Add shredded, cooked chicken, chicken broth and thawed mixed vegetables to the cooked noodles. Stir together.
In a separate bowl, stir together cream of chicken soup, sour cream, dry onion soup mix to taste, and 1 c. shredded cheddar. Gently fold sauce into noodle mixture and spread into prepared pan.
Sprinkle 1 1/2 to 2 c. shredded cheddar cheese on top, along with French fried onions (optional). Bake 25 to 30 minutes, or until hot and bubbly in the center.