Peel, core, and chop the apples into large chunks. Add to a slow cooker, along with the remaining ingredients. Stir until combined.
Set the slow cooker to "low" for 10 hours, stirring once partway through to avoid burning.
Transfer to a blender (or use an immersion blender) and blend until smooth.
Store in airtight jars, and spread on waffles, pancakes, biscuits, or cornbread, or scoop onto a sweet potato, over ice cream, or into a bowl of oatmeal.