Overnight Apple Butter

Turn a slow cooker on high and add all ingredients. Cover and cook for 1 1/2 hours, stirring occasionally. Mixture should be bubbling vigorously. Reduce heat to low and cook for 1 hour more. Remove and discard star anise pod.

With the lid set slightly ajar, continue cooking until apple butter is dark brown and thick, 7 to 9 hours more. Stir well and pass through a food mill or strainer, if necessary to remove any lumps.

Place six clean 1-pint or twelve clean 1/2-pint jars right side up on a rack in a boiling-water canner. Fill canner and jars with hot water, about 1 inch above tops of jars. Bring jars to a boil over high heat; boil for 10 minutes. Using a jar lifter, remove and drain hot sterilized jars one at a time, reserving hot water for processing filled jars. Place jars on a wire rack set over a rimmed baking sheet.

In another large pot filled with water, bring to a boil over high heat and reduce to a simmer, then add clean lids and lid rings. Simmer lids for 10 minutes; do not boil, as this may cause problems in sealing jars. Drain lids and set aside.

Divide apple butter evenly among sterilized jars, leaving 1/4 inch of space at top of each jar. Using tongs, place lids on jars. Using your hands, place rings on jars and tighten (but do not overtighten). Reheat water in the canner until it reaches at least 180 degrees, within 10 minutes of filling the jars. Place filled jars into the canner, one at a time, using a jar lifter securely positioned below neck of jar. Keep jars upright at all times.

Add more boiling water, if needed, so that water covers jars by at least 1 inch. Increase heat to high and cover. Once water begins boiling, heat jars for 10 minutes. Turn off heat and gently transfer jars to a wire rack set over a rimmed baking sheet, taking care not to tilt jars and spacing each jar at least 1 inch apart. Avoid placing jars on a cold surface or near a cold draft.

Let jars sit undisturbed until fully cooled, 12 to 24 hours. Do not tighten ring bands on the lids or push down on the center of the flat metal lid until jars have cooled completely.

Once jars have cooled completely, test to make sure each jar is completely sealed: Press down on the middle of the lid with a finger. If lid springs up when finger is released, jar is unsealed. Store sealed jars in a cool place. If any of the jars are unsealed, store in refrigerator and use within several days.