Place all ingredients into a 5-6 quart slow cooker. Cover and cook on high for 4 hours. Stir and continue cooking uncovered for 3 hours (or more) until apples are very tender and most of the liquid has evaporated. Let stand for one hour to cool.

Use an immersion blender or food processor to smooth and blend the apples. Ladle apple butter into half pint containers, leaving 1/2 inch space on top. Store in refrigerator for up to 3 weeks or put in freezer for up to a year.