French Onion Chicken Noodle Casserole

This French Onion Chicken Noodle Casserole is filled with delicious noodles smothered in a creamy French onion sauce. It’s easy to make with leftover or rotisserie chicken and your favorite onion dip!

Cook Time: 
90 Minutes
Prep Time: 
15 Minutes
Serving Size: 

1 pkg. Wewalka Puff Pastry Dough
2-3 Tbsp. vegetable oil
2 small boneless/skinless chicken breasts, or 2 cups cooked chicken
2 Tbsp. Italian seasoning
4 Tbsp. unsalted butter
2 extra-large yellow onions, or 1.5 pounds
2 springs fresh thyme
2 ½ cups chicken broth
1 cup beef broth
1 cup water
1 lb. Rotini pasta, or similarly sized pasta
1 cup onion dip mix
1 can cream of chicken soup
2 cups low moisture mozzarella cheese, shredded
1 egg + 1 splash cold water - Optional

  • Preheat oven to 400 °F. Slice the onions ¼ inch thick and set aside. A mandoline slicer makes this quick and easy. Shred the mozzarella and set aside. Low moisture mozzarella shredded from a block melts the best.
  • Butterfly the chicken and cut the seam to create two thinner pieces of equal size. Pat dry and season with Italian seasoning, salt, and pepper.
  • Heat the oil in a large pot or dutch oven over medium-high heat. Sear the chicken on each side for 4-5 minutes, until light golden brown. The bottom of the chicken will release from the pan once searing is complete. Carefully remove the chicken and leave 1 tablespoon of oil in the pot. Let the chicken rest for 5-8 minutes prior to cutting into bite-sized cubes.
  • Reduce heat to medium and melt the butter. Add the onion slices and toss to coat. Partially cover and stir occasionally. Reduce heat if they begin to cook too quickly. Allow them to reduce significantly over the course of 40 minutes, they will eventually turn a caramel color and begin to foam. Add the thyme during the last few minutes of cooking.
  • Add the chicken broth, beef broth, and water to the pot. Bring to a gently boil and add the pasta. Let the pasta gently boil uncovered for about 7 minutes, until no more than al dente. Stir occasionally.
  • Remove from heat. Add the onion dip, cream of chicken soup, mozzarella cheese, and cubed chicken. Stir to combine. Transfer to a lightly greased 9 x 13 casserole dish.
  • Remove the puff pastry from the fridge and gently unroll. Place it over the casserole dish and use a pairing knife to remove excess dough around the edges. Optional: Combine the egg + a splash of cold water, whisk to combine and brush a very light coating over the top of the pastry. Bake at 400 degrees for 20 minutes. Remove from the oven and serve!