ON THE STOVE TOP: Add all of the ingredients except the raisins to a pan and simmer on a medium-low heat, stirring every 5 minutes or so until the rice is soft and the pudding is thick, rich and creamy. Add the raisins and allow it to cook for 5 - 10 minutes more so they soften then serve.
The rice you use must be pudding rice or short grain rice. Look for grains that are plump and roundish. Any labelled as pudding rice will be fine, as will those labelled as risotto rice such as Arborio, Carnaroli or Vialone Nano.
This rice pudding will keep for 3 - 4 days in the fridge and can be warmed up gently again on the stove or in a microwave before serving.