Heat olive oil in a large skillet over medium heat.
Add diced onion and sauté until translucent, about 5 minutes.
Stir in minced garlic and cook for another minute.
Add ground beef to the skillet, breaking it apart with a spoon.
Cook until the beef is browned, about 7 minutes.
Drain excess fat if necessary.
Stir in crushed tomatoes and tomato paste.
Add oregano, basil, salt, and pepper to taste.
Simmer sauce on low heat for 20 minutes, stirring occasionally.
Serve hot over your favorite pasta, garnished with Parmesan cheese.