Preheat your oven to 400°F (200°C).

Dice the sweet potatoes into small pieces. In a large casserole dish, toss the sweet potatoes with olive oil, salt, black pepper, garlic powder, and dried rosemary. Ensure all potatoes are coated evenly.

Roast the sweet potatoes in the oven for about 30 minutes until tender and slightly caramelized.

While the sweet potatoes are roasting, heat a skillet over medium heat. Add the lean ground beef and cook until it starts to brown, stirring occasionally.

Once the beef is mostly cooked, add the diced onion to the skillet and cook until the onion becomes soft, about 5 minutes.

In the skillet, pour in the vegetable broth and heavy cream. Stir in the instant rice and cooked beef mixture. Mix well until everything is combined.

After the sweet potatoes are finished roasting, pour the beef and rice mixture over the sweet potatoes in the casserole dish. Cover the dish with aluminum foil and bake for 15 minutes.

After 15 minutes, remove the foil and sprinkle the shredded cheddar cheese on top. Bake uncovered for an additional 10 minutes, until the cheese is melted and bubbly.

Once done, take the casserole out and let it cool for 10 to 15 minutes. Garnish with chopped parsley before serving.