Heat 15g of butter in a large skillet over medium heat. Add your diced onion and sauté for 3-4 minutes until it becomes translucent and fragrant.

Add the ground beef to the skillet and cook, breaking it apart with a spoon, until it's evenly browned all over.

Stir in the minced garlic and cook for just another minute until it becomes aromatic.

Add the uncooked rice, beef broth, Italian seasoning, salt, and pepper to the skillet. Stir everything together to coat the rice.

Bring the mixture to a gentle boil, reduce the heat to low, cover the skillet, and let it simmer for 18-20 minutes.

While the rice finishes cooking, melt the remaining 30g of butter in a small saucepan. Add the milk, cheddar cheese, and Parmesan cheese, stirring until smooth.

Pour the cheese sauce into the skillet with the beef and rice mixture and stir until fully integrated.

Cook uncovered for 2-3 minutes to let the flavors meld together. Garnish with fresh chopped parsley if using.