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

In a skillet, heat olive oil over medium heat. Add chopped onion and minced garlic, sauté until softened.

Add ground beef to the skillet, cook until browned. Drain excess fat.

Stir in diced tomatoes, Italian seasoning, salt, and black pepper. Simmer for 15 minutes.

Add the cooked pasta to the meat sauce, stirring to combine. Serve hot, topped with grated parmesan cheese.