If you ask me what my favorite soup is, I’ll tell you it’s French onion. This dish combines all the ingredients of French onion soup into a chicken casserole. This is my French Onion-stuffed chicken casserole.

I wanted to make a few changes to the recipe, making the dish my own. The part of the French Onion Soup I love the most is the bread and the cheese. I think everyone would agree on the cheese, but the bread, people either love that component of the soup or they don’t. I love the way the toasted bread acts as a bed absorbing all the juices and becomes melt-in-your-mouth delicious.

Let’s get started with caramelizing the onions.

Prep Time: 15 minutes
Cook Time: 45 minutes
Total Time: 1 hour
Yields: 6-8 servings
Equipment: 1 (9 x 13 x 2-inch) baking dish, 1 (12-inch) sauté pan, paring knife, toothpicks, 1 meat-safe cutting board, instant-read thermometer, cutting board

Ingredients for the Caramelized Onions:
4 tablespoons of butter, unsalted and divided
1 tablespoon olive oil
4 large onions, halved and sliced thinly into half-moons
4 cloves of garlic, minced
2 tablespoons of Kosher salt
2 teaspoons of freshly ground black pepper
1 teaspoon of red pepper flakes (optional)
1 teaspoon of granulated sugar
1 tablespoon of fresh thyme leaves
2 tablespoons Sherry, substitute a dry white wine
1 (10.5-ounce) can of beef consommè (substitute unsalted beef broth)

Ingredients for the Stuffed Chicken Breasts:
6 boneless, skinless chicken breasts
2 teaspoons of garlic powder
1 teaspoon dried thyme
1 teaspoon of dried rosemary
1 tablespoon of Kosher salt
1 teaspoon of freshly ground black pepper
1 cup (8 ounces) of Gruyère cheese, freshly grated (substitute Mozzarella)
4 tablespoons of Pecorino Romano cheese, freshly-grated
1 tablespoon of fresh thyme leaves
Garnish:
Italian flat-leaf parsley, finely chopped for garnish

Ingredients for the Grilled Baguette:
1/4 cup of olive oil
1 teaspoon of Kosher salt
1/2 teaspoon of fresh ground black pepper
1 loaf of Fresnch baguette, 1/4-inch slices (yields 16 slices)

Instructions for the Grilled Baguette:
Preheat oven to 350°F.
Arrange the baguette slices in a single layer on a rimmed baking sheet. Brush the slices with olive oil and season with Kosher salt and black pepper. Bake until lightly toasted, 15 minutes. Let cool completely.

Instructions for the Caramelized Onions:
In a large sauté pan over medium-high heat, melt 2 tablespoons of butter. Add onions, granulated sugar, 1 tablespoon of Kosher salt, 1 teaspoon of fresh ground black pepper, red pepper flakes, and half the fresh thyme leaves. Cook for 5-8 minutes until tender.

Reduce the heat to medium and cook, while stirring occasionally, until the onions are caramelized and jammy, around 15 minutes. Add 1/4 cup of the beef consommé when the pan becomes too dry and continue stirring until onions are browned.

Pour in white wine (or Sherry), scraping the bottom of the pan to release any bits that stick to the bottom. Allow the wine to reduce, and cook for 1 minute until the sauce has thickened slightly.

Add the minced garlic and cook until fragrant, then cook for 1 minute. Turn the heat off and transfer to a large bowl to cool.

Instructions for the Stuffing of the  Chicken Breasts:
On a meat-safe board, lay out the six chicken breasts. Using a paring knife, cut a slit into the side of the breast 3 inches long and 1/ 1/2 inches deep. Be sure not to cut all the way through. You want to form a pocket for the stuffing. Do this to all the chicken breasts.

Spoon 1 to 2 tablespoons of the caramelized onions into each pocket. Next, the shredded cheese (approx. 1 to 2 tablespoons) is placed inside the pocket. Do not overstuff. Seal with toothpicks.

In a small mixing bowl, add garlic powder, dried rosemary, dried thyme, 1 tablespoon of  Kosher salt, and 1 teaspoon of freshly ground black pepper, and whisk to combine. Using the seasoning mix, season both sides of each chicken breast.

In the same sauté pan over medium-high heat, melt the remaining butter and olive oil. Cook the stuffed chicken breasts until golden brown, about 4 minutes per side. The chicken will finish cooking in the oven. Transfer the seared chicken breast to a large platter. Set aside.

Lightly spray the baking dish with non-stick cooking spray.

Transfer the remaining caramelized onions to the baking dish, spreading them out into one even layer.

With the pan still over medium-high heat, pour the remaining beef consommé into the sauté pan. *Deglaze the pan (using a wooden spoon, scrape all the chicken bits from the bottom of the pan). Reduce the heat and simmer until the broth reduces by half. There should be about 1/2 cup of sauce in the pan.

Add 1/4 cup of the sauce to the prepared baking dish, pouring it over the caramelized onions. This next step is optional: arrange the toasted baguette slices on top of the onions. The bread absorbs all the juices and acts as a bed for the chicken.

Lay the stuffed chicken breasts on top of the slices of grilled baguette. Spoon the remaining 1/4 cup of sauce from the pan over each chicken breast. Top with the remaining fresh thyme leaves. Bake covered for 15 to 20 minutes, remove the foil, and bake for an additional 5 minutes. Using an instant-read thermometer, the internal temperature of the chicken needs to read 165°F. 

Before serving, remove and discard all toothpicks.

To Serve: Place one of the stuffed chicken breasts onto a serving plate along with some of the onions, grilled bread, and pan juices. Sprinkle the top with freshly grated Pecorino Romano cheese and Italian flat-leaf parsley.

There you have it, my French Onion Stuffed Chicken Casserole.

Notes:
1) Linda Lou Hamel is not a nutritionist or dietitian, and any nutritional information shared is an estimate. If calorie count and nutritional value are important to you, I recommend running the ingredients through the online nutritional calculator of your choice. Calories and values can vary depending on the brands you choose.

2) *Deglaze: To dilute meat sediments in a pan and/or pot to make gravy or sauce, typically using broth or wine.

3) If you can’t find pre-toasted baguette slices, it’s easy enough to make them yourself, and they should be made in advance of this dish.

https://lindalouhamel.com/2019/07/10/summer-time-flowers-and-herbs/