Preheat oven to 350ºF (180ºC). Spread the apples in a single layer on a parchment paper-lined baking sheet.
Bake, stirring and rotating the pan occasionally, until the apples are deep amber color and caramelized, about 2 hours.
Let the apples cool, then add to a blender with the cider vinegar, sugar, cinnamon and cloves. Pulse until the mixture is pureed and smooth.
Remove to an airtight container and store refrigerated. Apple butter can be stored for up to 1 month.
Notes
Spread the apples in a single layer on the baking sheet and rotate the pan and stir the apples occasionally as they roast. You're looking for a deep amber color and caramelized edges, not just softened apples. That slow roasting concentrates their flavor and helps create a thick apple butter without needing to cook it down on the stovetop.