Bring a large pot of salted water to a boil. Add the rotini and cook until tender but still slightly firm in the center. Drain well and set aside.

Heat olive oil in a large skillet over medium heat. Add the ground beef and cook, breaking it apart with a spoon, until fully browned and no longer pink. Carefully drain any excess grease from the pan.

Sprinkle in the garlic powder, onion powder, Italian seasoning, crushed red pepper flakes if using, salt, and black pepper. Stir everything together so the beef is evenly coated with seasoning.

Pour the marinara sauce into the skillet and mix well. Let the sauce gently simmer for about 5 minutes, stirring occasionally, so the beef and sauce blend together.

Add the Velveeta cubes to the skillet. Stir continuously until the cheese melts completely and transforms the marinara into a smooth, creamy, rich sauce.

Add the drained rotini directly into the skillet. Toss thoroughly so every spiral is coated in the cheesy beef marinara mixture.

Sprinkle the shredded mozzarella evenly over the top, if using. Cover the skillet and let it sit for 2 to 3 minutes until the cheese melts, or place under the broiler briefly for a lightly golden top.

Finish with chopped parsley or basil if desired and serve hot while the cheese is perfectly melted and creamy.