Melt butter in a large oven-safe skillet (or Dutch oven) over medium heat. Add sliced onions and cook, stirring occasionally, until deeply caramelized – about 25-30 minutes. This step is crucial for flavor! Don't rush it.
2 tablespoons unsalted butter, 2 large yellow onions
Season chicken pieces with salt, pepper, garlic powder, and thyme. Add the chicken to the skillet with the caramelized onions and cook until browned on all sides.
1.5 lbs boneless, skinless chicken breasts, Salt and pepper, 1/2 teaspoon garlic powder, 1 teaspoon dried thyme
Pour in the chicken broth and bring to a simmer. If using, add sherry or white wine.
4 cups chicken broth, 2 tablespoons dry sherry or white wine
Stir in the uncooked orzo pasta. Ensure the orzo is submerged in the liquid.
1 cup orzo pasta
Cover the skillet with a lid or foil. Transfer to a preheated oven at 375°F (190°C) and bake for 20-25 minutes, or until the orzo is tender and the liquid is absorbed.
Remove the skillet from the oven. Top with Gruyère and Parmesan cheese.
1 cup Gruyère cheese, 1/2 cup Parmesan cheese
If desired, broil for 1-2 minutes until the cheese is melted and bubbly, watching carefully to avoid burning.
Let the casserole rest for a few minutes before serving. Enjoy your delicious French Onion Chicken Orzo Casserole!
