French Onion Stuffed Chicken Breasts
Golden chicken breasts stuffed with sweet, jammy caramelized onions and bubbling melted cheese—this dish tastes as amazing as it sounds!
It’s everything you love about French Onion Soup, transformed into an easy, elegant chicken dinner.
Don’t skip caramelizing those onions—the magic happens right there, and trust me, it’s absolutely worth it.
For the Chicken
- Chicken Breasts – Boneless, skinless chicken breasts are perfect for stuffing; they stay juicy and tender in the oven.
- Gruyere Cheese – Melts beautifully and gives that classic, gooey French onion flavor.
- Parmesan Cheese – Adds extra savory depth and balances the sweetness of the onions.
- Salt and Pepper – Enhances the chicken’s flavor and balances the dish.
- Olive Oil – Use it to quickly sear the chicken, giving it a beautiful golden-brown crust.
For the Caramelized Onion Filling
- Onions – Sliced thinly and slowly caramelized until sweet, jammy, and deep golden brown. Worth every minute!
- Butter and Olive Oil – A combination of both helps onions caramelize evenly without burning.
- Sugar – A pinch speeds up caramelization, enhancing the natural sweetness of onions.
- Fresh Thyme – Brings a subtle herby note, perfect with sweet onions.
- Balsamic Vinegar – Adds a slight tang and richness, lifting the flavors.
- Beef Broth – Keeps onions moist and saucy, mimicking that French Onion Soup quality.
- Garlic – Essential for depth of flavor; cook briefly to keep it aromatic.
French Onion Stuffed Chicken Breasts
Ingredients
- 2 tbsp unsalted butter
- 4 tbsp extra virgin olive oil, divided
- 4 large white onions, thinly sliced
- 1 tsp sugar
- 2 tsp fresh thyme
- 1 tbsp balsamic vinegar
- 1 cup beef broth, divided
- 3 cloves garlic, minced
- 4 boneless, skinless chicken breasts
- 1½ cups Gruyere cheese, grated
- ½ cup Parmesan cheese, freshly grated
- Kosher salt and freshly ground black pepper, to taste
Instructions
- Preheat Oven:Preheat your oven to 400°F. Lightly grease a 9x13-inch baking dish with butter or nonstick cooking spray.
- Caramelize the Onions:Heat 2 tablespoons butter and 2 tablespoons olive oil in a large skillet over medium-high heat. Add sliced onions and cook, stirring occasionally, until they soften. Reduce heat to medium if onions start browning too quickly.
- Deepen the Flavor:Sprinkle onions with salt, sugar, and fresh thyme. Continue cooking, stirring every few minutes, until onions turn deeply golden and jammy—around 30 minutes or longer. If onions become dry, gradually add up to ½ cup beef broth to keep them moist.
- Finish the Onions:Once caramelized, add balsamic vinegar to the pan, scraping any browned bits from the bottom. Stir in minced garlic and cook for an additional minute until fragrant. Remove from heat and set aside.
- Prepare the Chicken:Carefully cut a lengthwise pocket into each chicken breast, without slicing all the way through. Fill each pocket generously with about 2 tablespoons caramelized onions and a mixture of Gruyere and Parmesan cheeses. Secure pockets with toothpicks.
- Assemble the Dish:Spread remaining caramelized onions evenly in the prepared baking dish and stir in the remaining ½ cup beef broth.
- Sear the Chicken:Heat the remaining 2 tablespoons olive oil in a clean skillet over medium-high heat. Season stuffed chicken breasts with salt and pepper. Sear chicken until golden brown on each side, about 4 minutes per side. (Chicken doesn't need to cook completely during this step.)
- Bake to Finish:Place seared chicken breasts on top of onions in the baking dish. Spoon some onions and juices over each breast, and sprinkle with remaining cheeses. Bake uncovered for 15-20 minutes, or until chicken is fully cooked and cheese is melted and bubbling.
- Serve and Enjoy:Remove toothpicks before serving. Enjoy this delicious, hearty dish hot from the oven!
1. Can I caramelize the onions ahead of time?
Yes! Caramelizing onions takes time, so prepping them in advance is a game changer. Store them in an airtight container in the fridge for up to 3 days. When you’re ready to cook, just warm them up before stuffing the chicken.
2. How do I stop the cheese from leaking out?
To keep all that cheesy goodness inside:
✔ Use toothpicks to secure the chicken after stuffing.
✔ Don’t overstuff—too much filling makes it harder to seal.
✔ Sear the chicken first—it helps “lock in” the filling before baking.
3. What can I use instead of Gruyere?
No Gruyere? No problem! Swiss, mozzarella, or provolone are all great substitutes. Each one melts beautifully and keeps that rich, cheesy flavor.
4. How do I know when the chicken is fully cooked?
Use a meat thermometer! Insert it into the thickest part of the chicken—it should read 165°F (74°C). No thermometer? Just cut into the chicken; if it’s white and the juices run clear, you’re good to go!
5. Can I make this recipe ahead of time?
Absolutely! Stuff the chicken and keep it covered in the fridge for up to 24 hours before cooking. Let it sit at room temp for 15 minutes before searing and baking. Easy, right?
