<P> Various flavorings can be used, and can vary widely by taste and locality . Demerara sugar, golden syrup, Greek yoghurt and honey, and even langoustine tails and scallops have been employed for this purpose . A girdle of very cold milk or single cream is believed to be essential by some, traditionally served in a separate bowl to keep it cold . Glaswegians typically use canned evaporated milk and jam . Use of whisky, rum, or sherry have been reported . Cooking time can be adjusted to preference, but simmering for ten minutes is typical for non-instant oatmeal . Instant oatmeal, including flavored instant oatmeal, is common and can be prepared with the application of hot water . </P> <P> Historically, porridge was a staple food in much of Northern Europe and Russia . It was often made from barley, though other grains and yellow peas could be used, depending on local conditions . It was primarily a savoury dish, with meats, root crops, vegetables and herbs added for flavor . Porridge could be cooked in a large metal kettle over hot coals or heated in a cheaper earthenware container by adding hot stones until boiling hot . Until leavened bread and baking ovens became commonplace in Europe, porridge was a typical means of preparing cereal crops for the table . </P> <P> Porridge was also commonly used as prison food for inmates in the British prison system, and so "doing porridge" became a slang term for a sentence in prison . </P>

Where does the term doing porridge come from
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