Grease the inside of the pot half way up, with a little softened butter.
Add all of the ingredients into the pot and stir well.
Turn on the slow cooker and cook for 3 hours on low.
The pudding will be cooked when the rice is soft and fluffy, but retaining its shape without becoming mushy. You should still be able to stir through the pudding. Once cooked serve immediately.
Notes
How can I tell when it's cooked?
Similarly to dinner rice, taste the rice intermittently. If it still has too much bite or is crunchy, it'll need to be cooked for longer.
Slow cooker differences
Due to the variance in heat produced by different types of slow cookers, there may be some adjustments required to the stated cooking times. The slow cooker used in this recipe has a metal pot and cooks very quickly; more time will be required for slow cookers with ceramic pots.