French Onion Ground Beef and Rice Casserole

Heat the oven and warm the liquid

1. Preheat the oven to 400°F and lightly grease a 9x13 inch baking dish. Pour the French onion soup, condensed beef broth, and reduced sodium beef broth into a large saucepan. Warm over medium heat for about 5 minutes, until steaming. It does not need to boil, and it is fine if the soup looks thick at first because it will loosen as it heats.

Add the rice and liquid to the dish

1. Spread the uncooked rice evenly across the bottom of the baking dish. Carefully pour the hot liquid over the rice and give it a gentle stir so every grain is covered. Lay the butter slices over the top, then cover the dish tightly with foil so the steam stays inside.

Bake the rice

1. Place the covered dish in the oven and bake for 35 minutes. The rice will look softened but not fully cooked, and some liquid will still be visible. This is exactly right, because the rice finishes cooking later.

Caramelize the onion

1. While the rice bakes, warm the olive oil in a large skillet over medium heat. Add the diced onion and cook, stirring now and then, for 8 to 10 minutes, until soft, golden, and lightly browned at the edges. Move the onion to a plate and set it aside.

Brown the beef

1. Turn the heat up to medium-high and add the ground beef, garlic powder, and black pepper to the same skillet. Cook for 6 to 8 minutes, breaking the meat into small crumbles with a spoon, until no pink remains and the beef reaches 160°F. Drain off any excess fat, then return the skillet to the stove.

Cook the mushrooms

1. Add the sliced mushrooms and dried thyme to the skillet. Cook for 5 to 6 minutes, stirring only occasionally, until the mushrooms are golden brown and fragrant. They will release water first and then brown, so a little patience helps here. Stir in the minced garlic for the last 30 seconds, then add the beef and onion back to the skillet along with the soy sauce and Worcestershire sauce. Stir until everything is evenly coated and glossy.

Combine with the partly baked rice

1. When the 35 minutes are up, carefully remove the dish from the oven and leave the oven on. Lift off the foil, watching for hot steam, and stir the beef and mushroom mixture into the rice. Spread everything into an even layer.

Finish baking the rice

1. Return the uncovered dish to the oven and bake for 25 minutes, until the rice is tender and most of the liquid has been absorbed. If it still looks soupy, bake for 5 more minutes. The mixture will continue to thicken as it rests.

Add the topping

1. Sprinkle the Gruyere and mozzarella evenly over the casserole, then scatter the crispy fried onions on top. Bake for 5 to 7 minutes, until the cheese is melted and bubbling and the onions are golden brown. Let the casserole rest for 5 minutes before serving so it sets and is easier to scoop.