Cook the penne pasta according to the package instructions. Drain and set aside.

In a large pan, heat the olive oil over medium heat. Add the chopped onion and cook until it becomes translucent, about 5 minutes.

Add the minced garlic and cook for an additional 1-2 minutes until fragrant.

Stir in the canned diced tomatoes, dried oregano, dried basil, salt, and pepper. Simmer for about 10 minutes, allowing the sauce to thicken.

Add the cooked penne pasta to the tomato sauce and toss to combine. Cook for an additional 2-3 minutes to heat the pasta through.

Serve the tomato penne pasta garnished with fresh basil leaves. If desired, sprinkle with grated Parmesan cheese before serving.