1Preheat your oven to 375°F (190°C).
Cook the penne pasta according to the package instructions until al dente. Drain and set aside.
In a large skillet, heat the olive oil over medium heat. Add the chopped onion and sauté until translucent, about 5 minutes.
Add the minced garlic and cook for another 1-2 minutes until fragrant.
Stir in the tomato sauce, dried oregano, salt, and black pepper. Let the sauce simmer for about 10 minutes.
In a large mixing bowl, combine the cooked penne pasta with the tomato sauce. Mix well to ensure the pasta is evenly coated.
Transfer half of the pasta mixture to a baking dish. Sprinkle half of the shredded cheddar and mozzarella cheese over the pasta.
Add the remaining pasta mixture on top and sprinkle the rest of the cheese over it.
Bake in the preheated oven for 20-25 minutes, or until the cheese is melted and bubbly.
Remove from the oven and let it cool for a few minutes before serving. Enjoy your Cheesy Baked Penne!