01 -
Set oven to 350°F (175°C) and lightly grease a 9×13-inch baking dish.
02 -
In a large skillet, cook ground beef over medium heat until browned. Drain excess fat if needed.
03 -
Add sliced onions to the pan and cook until softened and caramelized, about 5 minutes. Stir in garlic and cook for 30 seconds.
04 -
Stir in Worcestershire sauce, French onion soup, cream of mushroom soup, beef broth, rice, salt, pepper, and thyme. Mix well.
05 -
Transfer the mixture to the prepared baking dish. Cover tightly with foil.
06 -
Bake for 45 minutes, then remove foil, stir, and check if rice is tender. If needed, bake another 10 minutes.
07 -
Sprinkle cheddar, mozzarella, and crispy fried onions over the casserole. Bake uncovered for 5-10 more minutes, until cheese is melted and bubbly.
08 -
Let it sit for 5 minutes, then serve.