First make the cranberry compote. Place all of the ingredients for the compote into a medium sized pan and heat gently. Simmer for around ten to fifteen minutes until the cranberries have softened and the compote has thickened. Leave aside to cool. Remove the star anise before using.
Now make the pudding. Place the softened butter, caster sugar, flour, eggs and vanilla bean paste in a bowl and beat well until smooth.
Grease a pudding bowl with butter, then place enough of the cranberry compote in the base of the bowl to cover it (about four spoonfuls).
Place the pudding mixture on top. Use clingfilm to seal the pudding bowl.
Get your slow cooker ready. Note: I used my large 5.7 litre Crockpot for this recipe, as I can get a pudding bowl in there.
Boil a kettle and pour the boiling water into the slow cooker ceramic pot.
Place the pudding bowl, covered with clingfilm, into the water.
Place the lid back on the slow cooker and cook on high for 2 to 2.5 hours, until the pudding has risen in the bowl and the top centre of it looks firm.
Allow to cool, then remove the pudding bowl from the slow cooker using oven gloves.
Invert the pudding onto a plate and spoon over a little more of the cranberry compote, to serve. Serve warm with custard or cream.