Preheat oven to 350ºF. Lightly spray a 9x13-inch pan with cooking spray.
Cook egg noodles according to package directions. Drain and set aside.
Cut chicken into small bite-sized pieces. Toss with fajita seasoning. Set aside.
In a large skillet, heat olive oil over medium-high heat. Add peppers and onions. Cook for 3 to 5 minutes. Add fajita coated chicken and cook for an additional 5 minutes.
In a large bowl. combine cream of chicken soup, sour cream and 1-½ cups of cheese. Stir in cooked chicken and vegetables. Stir in cooked noodles. Pour into prepared 9x13-inch pan. Top with remaining cheese.
Bake for 25-30 minutes, until bubbly.
