To begin, cook the pasta according to package directions. Meanwhile brown the beef with the onion and garlic powders in a large skillet until cooked through. Drain off any excess grease if necessary. Add in the marinara and sour cream, stir to combine. Add in your cooked pasta, stir to coat. Top with the shredded cheese and cover. Let it sit for 5 minutes or until the cheese is just melted. Serve with a tossed salad. Enjoy!