Black pudding, as made in the UK, is a blend of onions, pork fat, oatmeal, flavorings - and blood (usually from a pig). As long as animals have been slaughtered to provide food, blood sausages like black pudding have been in existence. Other varieties of blood sausage include blodpølse in Norway and Denmark, boudin noir in France, tongeworst (with added pigs tongues) in the Netherlands, zwarte pens or beuling in Belgium, blóðmör in Iceland, boudin rouge in Creole and Cajun areas of the US, morcela and chouriço de sangue in Portugal, morcilla in Spain and Latin America, krvavica in Eastern Europe, sângerete in Romania, prieta in Chile, rellena or moronga in Mexico, doi in Vietnam, ragati in Nepal, mustamakkara in Finland, verivorst and verikäkk in Estonia and kaszanka in Poland. Seasonings and fillers vary from maker to maker and country to country, but black pepper, cayenne pepper, mace, herbs, and coriander are frequently used flavorings. These are added to the blood, oatmeal and suet/fat mixture, which is used to fill the casings. Posted from an online source in response to a recipe request. It isn't an easily made recipe due to lack of sources for absolutely and pristinely fresh ingredients.