Description
French Onion Stuffed Chicken Casserole is a hearty and flavorful dish featuring juicy chicken breasts stuffed with caramelized onions and a blend of Gruyère and Parmesan cheeses. The chicken is seared for a golden crust and then baked atop a bed of rich, balsamic-enhanced onions that soak up all the savory juices, making for a comforting and elegant meal perfect for weeknight dinners or special occasions.
Ingredients
Caramelized Onions
- 2 tablespoons unsalted butter
- 4 large onions, halved and thinly sliced
- 1 pinch salt, to season
- 1 pinch pepper, to season
- 1 teaspoon fresh thyme, chopped (divided)
- 2 tablespoons balsamic vinegar
- 2 cloves garlic, minced
- 1/2 cup beef broth (or stock), divided
Chicken and Stuffing
- 1 tablespoon olive oil
- 4 boneless skinless chicken breasts
- 2 teaspoons garlic powder
- 1 teaspoon ground thyme
- 1 cup Gruyère cheese, shredded (or mozzarella cheese)
- 4 tablespoons Parmesan cheese, freshly grated
- 1 teaspoon fresh thyme, chopped (remaining)
Instructions
- Prepare the Oven and Baking Dish: Preheat your oven to 400°F (200°C) and lightly grease a 9×12-inch baking dish; set it aside for later use.
- Caramelize the Onions: Melt the butter in a large skillet over medium-high heat. Add the sliced onions and season with salt, pepper, and half of the chopped fresh thyme. Cook for 5–8 minutes until the onions soften.
- Cook Onions Until Jammy: Lower the heat to medium and continue to cook the onions, stirring occasionally, for about 15 minutes until they become caramelized and jam-like. Add 1/4 cup of broth as needed to prevent drying and enhance softness.
- Deglaze and Flavor: Pour in the balsamic vinegar to deglaze the pan, scraping up any browned bits. Allow the mixture to cook for about 1 minute until it thickens slightly.
- Add Garlic and Cool: Stir in the minced garlic and cook until fragrant, around 1 minute. Remove from heat and let the onion mixture cool slightly.
- Prepare the Chicken: Slice each chicken breast horizontally to create pockets. Season the chicken inside and out with salt, pepper, garlic powder, and ground thyme.
- Stuff the Chicken: Place 1–2 tablespoons of the caramelized onions into each pocket. Then stuff with a mixture of shredded Gruyère and Parmesan cheese. Secure the pockets with toothpicks to keep the filling inside.
- Prepare Onion Bed: Transfer the remaining caramelized onions to the greased baking dish. Mix in the remaining 1/4 cup of beef broth and spread evenly.
- Sear the Chicken: Heat olive oil in the same skillet over medium-high heat. Sear each stuffed chicken breast for about 4 minutes per side until golden brown. Note that the chicken will not be fully cooked in this step.
- Bake the Casserole: Arrange the seared chicken breasts on top of the onion bed in the baking dish. Spoon some of the pan juices over each breast, sprinkle with the remaining chopped thyme, then bake in the preheated oven for 15–20 minutes until the chicken is cooked through.
- Serve: Remove toothpicks from the chicken. Serve hot with the caramelized onions and pan juices spooned over the top for maximum flavor.
Notes
- You can substitute mozzarella cheese for Gruyère for a milder flavor.
- Use chicken broth instead of beef broth for a lighter taste, though beef broth adds richer depth.
- Make sure to not overcook the chicken during searing as it continues cooking in the oven.
- If you prefer a stronger onion flavor, use red onions instead of yellow or white.
- Remove toothpicks carefully before serving to avoid accidents.
