Put the sifted flour, baking powder and salt into a bowl. In another bowl, put the sugar and butter. rub the butter and sugar together really well until they become consistent. Add one egg and a tablespoonful of flour. Fold it into the mixture. Repeat with the second egg. Now put in the remaining flour, the raisins and a dribble of milk to help the moistness. Finally, add the cinnamon.
Your preparation should look something like this:
Put the mixture into a heatproof bowl of about 750ml seal it with tin foil and put it into boiling water, making sure no water is high enough to not enter the bowl (I put a jam pot lid in the bottom of the saucepan to keep it up).
You will need to boil it for about 2 hours.