For pickled pears, peel and coarsely chop ginger. Bring to a boil with cloves, cinnamon, brown sugar and apple cider vinegar while stirring, simmer for 10 minutes at low heat, then let cool.
Peel and halve pears, scoop out core with a baller.
Place the pears in a large bowl, pour the syrup over them and leave to infuse for one night, covered with baking paper.
Now pour the syrup through a sieve into a large pot and remove the spices. Add the pears to the syrup and cook uncovered for 20-25 min at a moderate temperature until just tender.
Put pickled pears in a canning jar, fill with boiling hot syrup and close tightly.