This easy French Onion Chicken Bake is a fun twist on the classic soup. Juicy, tender chicken breasts are infused with the flavors of French onion soup, like caramelized onions, beef broth, and melted gruyere cheese. It's a delicious meal that tastes like it was cooked all day, but only takes about an hour.
Peel the onions, cut in half, and slice into thin half-moons
In a large skillet over medium-high, heat the olive oil and melt butter until foamy.
Add sliced onion and cook, stirring occasionally, until they start to turn golden brown, around 15 minutes.
Stir in the beef broth, balsamic vinegar, and Worcestershire sauce. Continue to cook until liquid is reduced, about 5 minutes. Remove from heat.
Stir in the garlic powder, salt, pepper, and thyme.
Preheat oven to 400°
Use butter or olive oil to grease a 9" x 13" baking dish.
Spread half of the caramelized onions on the bottom of the baking dish.
Arrange the chicken breasts evenly over the onions in the baking pan and season them with salt and pepper.
Top the chicken with the remaining caramelized onions.
Top the chicken and onions with the shredded cheese.
Bake 30-40 minutes, until chicken is cooked to an internal temperature of 165°
Notes
Use a different cut. Instead of chicken breast, try boneless skinless chicken thighs or tenders.
Temp the chicken. The easiest way to know when the chicken breasts are done is to probe them with an instant-read thermometer. Chicken is fully cooked when it reaches 165°.
Add some Parmesan. To add a little extra saltiness, sprinkle some grated Parmesan cheese over the gruyere before baking.
Boost the flavor. For an extra depth of flavor, deglaze the bottom of the pan with a little white or red wine to pull up all those flavorful browned bits and infuse them into the sauce.
Make it one pan. To make clean up easy, I sometimes make this delicious French onion chicken bake in an oven-safe skillet that can go from stovetop to oven. (like a cast iron pan).
Storage. Allow the casserole to cool to room temperature, then transfer to an airtight container and store in the fridge for 3-4 days.
To freeze. The leftovers can be frozen in freezer-safe containers, then thawed, and reheated.