Follow these steps, and you’ll have a delicious casserole ready in no time:

1. Preheat your oven to 375°F (190°C).
2. In a large skillet, heat the olive oil over medium heat. Add the diced onion and cook until translucent, about 3-4 minutes.
3. Add the ground beef to the skillet, breaking it apart with a spatula. Cook until browned, about 5-7 minutes. Drain excess fat.
4. Stir in the garlic powder, onion powder, salt, and black pepper, mixing well to combine.
5. Add the rice to the skillet, followed by the beef broth and cream of mushroom soup. Stir until everything is well incorporated.
6. If using, add the frozen peas or mixed vegetables to the mixture.
7. Transfer the mixture to a greased 9×13-inch baking dish. Cover tightly with aluminum foil.
8. Bake in the preheated oven for 30 minutes. Remove the foil, sprinkle the cheddar cheese over the top, and bake for an additional 10-15 minutes, until the cheese is melted and bubbly.
9. Let the casserole rest for 5 minutes before serving. This allows the flavors to meld together beautifully.

As my grandmother always said, “It’s the little pauses that make the meal.” Letting the casserole rest is that little pause, ensuring every bite is as flavorful as it can be.