In a large pot of boiling salted water, cook the penne until al dente.
Meanwhile, in a large, deep skillet, heat 1/4 cup of the olive oil. Add the garlic and crushed red pepper and cook over moderate heat until golden and fragrant, about 3 minutes. Add the crushed tomatoes, oregano and a pinch of salt and bring to a boil. Simmer over moderate heat, stirring occasionally, until slightly reduced, about 8 minutes.
Drain the penne, reserving 1/3 cup of the pasta cooking water. Add the penne to the skillet and toss well. Add the reserved pasta cooking water, the remaining 2 tablespoons of olive oil and the parsley, season with salt and stir well. Transfer the pasta to shallow bowls and serve with the pecorino cheese.