1) Add the cream to your slow cooker and set on the lowest heat. Check your manual. You don’t want the cream to get above 180 degrees F. Ideally it would cook between 165-180 degrees F. Cover and let cook for 8 hours.
2) Remove from heat and transfer cream to the fridge to cool down for four hours. Be careful to not disturb the skin on top of the cream too much.
3) Once the cream is really chilled down, use a spoon to scrape the clotted cream layer off the top of the cream. Transfer it to a bowl and stir it together. There will be some cream gunk at the bottom of your slow cooker that you can just discard.
4) Transfer the clotted cream to an air-tight container and use it within a week on any sort of pastry!