If you want to find a *genuine* Italian restaurant in the UK, the telltale sign to look for is one that doesn't have pizza on the menu [in Italy, pizzas are only sold in dedicated pizzerias], or indeed have pasta featured on menus as a main course! No self-respecting Italian restaurant in Italy would be seen dead doing either!
In proper Italian restaurants, pasta dishes ONLY feature as first courses (served in small portions) - NEVER as mains. End of. And you'll *never* see Spaghetti Bolognese, as it simply doesn't exist in Italy. Tagliatelle al Ragu is the real deal. In good restaurants, you'll also rarely find lasagne on the menu, as it's normally something Italians eat at home.
Therefore a typical menu in a genuine/authentic Italian restaurant will start with options for antipastos (cured meats, pickles, bruschetta, etc), then first courses, which will either be forms of soup, rice or pasta. Then will come the main courses, but crucially split into meat or fish dishes, listed in dedicated sections, with salad, vegetable and potato side-dishes also listed separately, then desserts and cheese.
So.... If your favourite Italian restaurant has a laminated menu (the contents of which almost never change), and which is dominated primarily by pasta and pizza, with only a token meat or fish dish, neither of which is particularly exciting, then you can safely assume that it's 'plastic Italian', and you can do MUCH better!
Marco.