Peel and core the apples, and cut them into quarters. Combine the apples and the remaining ingredients in your crock pot.
Cook on low for about 6-8 hours, until the apples are very soft.
Use an immersion blender, a regular blender or a food processor to puree the apple butter until silky smooth.
Return the apple butter to the crock pot and cook on low for another 1-2 hours, until thickened.
Ladle the apple butter into glass jam jars. If refrigerated, you should consume the apple butter within about 3 months or less. If you have the freezer space, you can freeze the jars for up to 1 year. Or, follow standard canning procedures to can and seal the jars, making them safe to store in your pantry for 1-2 years.