Heat the olive oil in a large saucepan over medium heat. Stir in the onion and cook and stir until softened, about 5 minutes. Add the garlic and chilli flakes and cook, stirring, for an additional minute.
Stir the vodka, crushed tomatoes and light cream into the onion mixture, turn heat to high and bring sauce to a boil. Reduce heat to low, stir in the Romano cheese and simmer for 2 hours, stirring occasionally. Season finished sauce with salt and pepper.
Fill a large pot with lightly salted water and bring to a rolling boil over high heat. Once the water is boiling, stir in the penne and return to a boil. Cook the pasta uncovered, stirring occasionally until the pasta has cooked through but is still firm to the bite, about 10 minutes. Drain well in a colander set in the sink. Transfer pasta to a large bowl and pour vodka sauce over, tossing to coat pasta.