Core and slice the apples into ¼” pieces, leaving the peels on for extra flavor and texture. Add the apples to the crockpot.
Sprinkle in the brown sugar, granulated sugar, cinnamon, cloves, and salt. Toss everything together to coat the apples evenly.
If using a vanilla bean, slice it open and scrape the seeds (caviar) into the pot, then add the pod. If using vanilla extract, simply pour it in.
Cover and cook on low for 10-12 hours on low heat (or high for 5 hours) until the apples are incredibly soft.
Once done, use an immersion blender to puree until smooth, or carefully transfer to a blender.
Transfer to four 1 pint mason jars. Store your apple butter in glass jars in the refrigerator for up to 2 weeks, or opt for canning if you'd like it to last longer.
If canning, can in a hot water bath using the traditional method for 10 minutes. Enjoy!