Easy French Onion Chicken Casserole

French Onion Chicken Casserole is the most delicious remix of one of my favorite soups out there! The caramelized onions pairs perfectly with the juicy chicken breasts, and the delicious Swiss cheese. This dish is the ultimate date night main course that will have your entire family or dinner guests in awe of your abilities!

French Onion Chicken Bake

There is nothing more mouthwatering than the glorious melted cheese on classic French onion soup or refreshing French onion dip, but that isn’t enough for a meal!

I can’t blame you for trying to make that your entire supper though; I can’t ever get enough of French onion soup either.

In a successful attempt to make this tasty soup a full meal, I put together this French onion chicken recipe to serve at your next get together with guests or your partner!

With the green beans that are cooked to perfection, and the sweet crunch of the onions, this recipe is unbeatable.

You will be satisfying your veggie needs, protein goals, and carbohydrate cravings in one flavorful easy dinner recipe!

If you like this one, you will love my Biscuits and Gravy Casserole and my Million Dollar Chicken Casserole. Both rich and satisfying!

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Ingredients Needed

• Chicken – Cooked, shredded chicken is perfect. I love to use rotisserie chicken for extra flavor. Great with pork chops too!
• Mayonnaise – I always suggest using Duke’s mayonnaise, but any other mayo will be fine! Low fat or regular are both great.
• Sour cream – Sour cream is the secret ingredient to delicious creaminess! Regular works best but you can sub low fat or fat free. Greek yogurt is a great substitute.
• Heavy cream – Heavy cream is commonly substituted for half and half.
• Caramelized onions – Caramelized onions can be done in a saucepan with about one tablespoon of olive oil per onion. At medium heat, stir every 30 seconds until golden brown.
• Beef bouillon granules – Alternatively, beef broth or broth concentrate (paste) will be just as good!
• Green beans – Choose French cut green beans to continue meeting the classic flavor.
• Swiss cheese – Substitute Swiss cheese for shredded Parmesan cheese. Mozzarella cheese works in a pinch.
• Spices – Garlic powder, or minced garlic, and rubbed sage. Poultry seasoning works in a pinch.
• Grands Buttermilk Biscuits – Buttermilk is a classic, but any canned biscuits will do. You can also make your own.
• Parsley – Although it is optional, this meal tastes like a five star restaurant and should look like it too! Parsley can garnish the top.
• Pantry Staples – salt, black pepper, melted butter, cooking spray.

How to Make the French Onion Chicken Casserole

1. Preheat the oven to 350°F, and prep a 9×13 baking dish with cooking spray.
2. In a large mixing bowl, combine the chicken, mayo, sour cream, heavy cream, bouillon, salt, pepper, garlic powder, and sage. Lastly mix in green beans and caramelized onions.

3. Spread the chicken mixture into the prepared casserole dish, then bake at 350°F for 20 minutes.
4. Remove from the oven and evenly spread quarters of the rolls on top of the casserole. Brush with melted butter.

5. Return to the oven and bake for 20 minutes or until the biscuits are cooked and golden brown.
6. Remove and garnish with chopped parsley if desired. Enjoy!

For the full recipe and detailed baking instructions, please see the recipe card at the end of this post.

Can I substitute the buttermilk biscuits?

The biscuits are one of the ingredients that hold this recipe together, though you could certainly substitute it.

Some favorite substitutes of mine would be to go with classic French baguette slices, or brioche buns. You’d be surprised with the dynamic and sweet flavor of brioche could add to the recipe!

What can I serve with French Onion Chicken Casserole?

This delicious casserole can best be plated with a side of carrots, a rice casserole or a side salad.

Or, serve with a French baguette to really hit home with the addictive flavor of French onion soup.

How do I store French Onion Chicken?

This casserole will keep great in the refrigerator for four to five days. Wrap tightly in plastics wrap or aluminum foil or store in an airtight container.

When you’re ready to serve, I always love to add a pat of butter to the top of the biscuit and some fresh parsley. 

Can you freeze this?

The beauty of casseroles is that they freeze very well and are ready to serve after thawing then baking. This casserole is just the same!

French onion chicken casserole does great when frozen. This will be fine in your freezer for up to two months. Remember to wrap tightly and thaw before baking!

Best Casserole Tips

• Use cooking spray to avoid sticking and easy cleanup.
• Make a super easy version using cream of chicken soup!
• Lunch for tomorrow? Add a small tablespoon butter to the top of the biscuit to refresh that warm flavor.
• Leftover French onion chicken will be happy in an airtight container for up to five days or in the casserole dish with plastic wrap for up to four days.
• Prep ahead and it is perfect for a busy night.
• Leave off the biscuits and use cooked egg noodles or delicious french fried onions.
• Make and freeze in advance for up to two months to have a quick dinner ready to bake!

If you love this recipe as much as I do, pin this to your favorite casserole Pinterest board and share it on your favorite social media channels!

French onion soup is a beloved soup, but not nearly as filling or tasty as french onion chicken casserole! This easy to make and great freezable casserole the whole family will love and have your hungry guests taking a second serving!

Easy Casserole Recipes

• Salisbury Steak Casserole
• Chicken Spaghetti Casserole (Easy)
• Ultimate Chicken Casserole

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