Bring a large pot of salted water to a boil and cook the pasta according to package instructions until al dente.

While pasta cooks, heat olive oil in a large skillet over medium-high heat.

Add the ground beef and diced onion to the skillet. Cook until beef is browned and onions are translucent, approximately 7 to 10 minutes.

Drain the rendered fat from the skillet.

Add the minced garlic, oregano, salt, and pepper to the beef mixture and cook for 1 minute until fragrant.

Stir in the marinara sauce and reduce heat to low, simmering for 5 minutes.

Drain the cooked pasta and add it directly into the skillet with the beef and sauce.

Toss thoroughly to coat the pasta and serve topped with parmesan cheese.