Creating French Onion Chicken is easy when you follow these simple steps:

1. Preheat Oven: Preheat your oven to 400°F (200°C).
2. Cook Onions: In a large skillet, heat the olive oil and butter over medium heat. Add the sliced onions and a pinch of salt; sauté until caramelized (about 15-20 minutes).
3. Season Chicken: While the onions are cooking, season the chicken breasts with salt, pepper, and thyme on both sides.
4. Sear Chicken: In a separate pan, sear the seasoned chicken breasts in a bit of oil over medium-high heat for about 5 minutes on each side, or until golden brown.
5. Combine Ingredients: Once the onions are caramelized, add the beef broth to the skillet, stirring to combine with the onions.
6. Bake Chicken: Transfer the chicken breasts into a baking dish. Pour the onion and broth mixture over the chicken.
7. Add Cheese: Sprinkle the shredded Gruyère cheese generously over the chicken and onions.
8. Bake in Oven: Place the dish in the preheated oven and bake for 20-25 minutes, or until the chicken reaches an internal temperature of 165°F (75°C).
9. Garnish: Once cooked, remove from the oven and garnish with fresh parsley before serving.

These simple steps will take you through creating an unforgettable dinner that will delight everyone at your table.