1. In a large skillet, melt butter over medium heat and sautée minced garlic and diced onion until fragrant.

2. Add ground beef, season with salt and pepper, and cook until browned.

3. Stir in the cooked rice, letting it absorb the garlic butter mixture.

4. In a saucepan, melt butter and whisk in flour to form a roux.

5. Gradually whisk in milk and cream until smooth and thickened.

6. Add cheddar and Parmesan cheeses, stirring until melted and creamy.

7. Pour cheese sauce over beef and rice, stirring well to combine.

8. Let simmer for a few minutes until heated through and thickened.

9. Serve hot straight from the skillet.