Most of these items can be found in a supermarket; as in all serious forms of cookery, though, what matters most is quality and freshness of ingredients, so we recommend that serious Pringlers look to local suppliers of fresh vegetables and herbs, and try specialist delicatessens for unusual items, or perhaps even ready-made sauces and pastes if they cannot make their own. Paxton & Whitfield in Jermyn Street is our supplier of choice for cheeses, and nearby Fortnum & Mason or Harrods Food Hall is good for almost everything else. Olga Stores in Penton Street, Islington (020 7837 5467), is a good source of Italian cured meats and Mediterranean sauces. Pringles, of course, are the same everywhere.