Add oats, water, cider, apples, honey, cinnamon, nutmeg, allspice, and salt to a heavily greased or lined slow cooker crock and stir to combine.
Cover and cook on low for 6-8 hours. Actual cooking time will vary depending on your slow cooker, so check to see if it's done after 5 hours and adjust cooking time accordingly.
The cooking times for this recipe were based on using Steel Cut Oats only. Please do not substitute any other type of oats for this recipe.
It very important to either line or heavily grease the sides of your slow cooker crock before preparing this recipe. If you skip this step, the oats will stick to the sides and will be very difficult to remove.