Cover and cook on high for about 3-4 hours or until apples are soft enough to mash.
Mash apples with a potato masher until it is the consistency of applesauce.
Stir in brown sugar and white sugar (a little at a time, since you may not need all of it depending on how sweet your apples are)
Stir in cinnamon, nutmeg, and clove. (taste and adjust to your liking. It should be quite sweet since this will be a spread)
Cover and cook on low for 3-4 hours, stirring occasionally.
Stir, remove the lid a little so that steam can escape and cook on high for 2-3 hours or until the liquid is absorbed and the apple butter passes the done test (see note)
Cool and store in an airtight container in the fridge.
Cooking times: Cooking times will vary based on the apple used. Some apple varieties are juicer or firmer than others. Cooking times will also vary based on the crock pot size. To check for doneness: Spoon out some of the apple butter, turn the spoon upside down. The apple butter should cling to the spoon without falling off right away. If it does fall off, continue cooking to remove more of the liquid. Alternatively, you can spoon a mound of apple butter on a plate and watch to see if liquid forms around it.