6 pounds Granny Smith or other tart apples, unpeeled, cored, and sliced
2 1/2 cups apple cider
2 cups firmly packed light brown sugar
2 strips of lemon zest, each 2 1/2 inches long
1 tablespoon cinnamon
1 teaspoon ground allspice
1/2 teaspoon ground cloves
1/2 teaspoon salt

In a large saucepan cook the apples in the cider over moderate heat, stirring occasionally, for 30 minutes, or until tender. Puree them through the medium disk of a food mill into another saucepan and add the remaining ingredients.
Cook the mixture over very low heat, stirring occasionally, for 2 1/2 to 3 hours, or until very thick. Discard the lemon zest and spoon the mixture into 2 sterilized 1-pint Mason-type jars, filling them to within 1/2-inch of the top. Wipe the rims with a dampened cloth and seal the jars with the lids.

Put the jars in a water bath canner or a rack in a deep kettle and add enough water to cover the jars by 2 inches. Bring to a boil and process, covered, for 10 minutes. Transfer the jars with canning tongs to a rack and let them cool. Let the apple butter mellow in a cool, dark place for at least 1 week