Moist, plump prunes work best here. Serve with roast pork or game, or use as a stuffing for pork tenderloin.
Combine sugar and water in a medium saucepan. Bring to a simmer over low heat, stirring to dissolve the sugar. Simmer, washing down the sides of the pan with a pastry brush dipped in cold water, for 1 minute. Remove from the heat and stir in brandy. Set aside to cool to room temperature.
Divide the prunes among four 1-pint or two 1-quart sterilized jars. Put some orange zest and allspice berries into each jar. Pour the brandy syrup over the prunes, adding additional brandy, if necessary, to cover the prunes completely. Close lids and let the jars stand in a cool, dry place for at least 1 month to allow flavors to blend.
Make Ahead Tip: Store in a cool, dry place for up to 1 year.