01 -
Preheat oven to 175°C. Lightly grease a 33 x 23 cm baking dish.
02 -
Heat a large pot over medium-high heat. Add ground beef and cook, breaking up with a spoon. Season with salt, pepper, and Italian seasoning. Cook until browned and cooked through.
03 -
Drain excess fat from the beef. Transfer cooked beef to a plate and cover with foil to keep warm.
04 -
In the same pot, melt 2 tablespoons butter over medium heat. Add diced onion and cook for 5 minutes until softened. Add minced garlic and cook for 1 minute until fragrant.
05 -
Add beef broth, remaining 1 tablespoon butter, and uncooked rice to the pot. Stir well. Bring liquid to a boil, then reduce to a simmer. Cover tightly and cook for 10 minutes.
06 -
Add sliced mushrooms to the pot, replace the cover, and continue simmering for 5 to 10 more minutes. Follow the rice package instructions for precise timing. Do not stir the rice.
07 -
Remove pot from heat. Keeping it covered, allow rice to stand undisturbed for 10 minutes so any rice at the base loosens naturally.
08 -
Add reserved ground beef, cream of mushroom soup, milk, sour cream, and half of the cheddar cheese to the pot. Stir gently until evenly combined.
09 -
Transfer the mixture to the prepared baking dish. Sprinkle remaining cheddar cheese evenly on top.
10 -
Cover the dish with foil and bake for 20 minutes until cheese is melted and casserole is bubbling. Serve hot.