You will need a saucepan large enough to fit all the pears snugly.
Combine all the ingredients, except the pears, in the saucepan and bring to the boil.
Add the pears, ensuring they are all submerged. It is useful to cover them with baking paper and place a plate on top that won’t squash the pears, but will gently keep them submerged. Simmer, covered, for 1 hour.
Remove the lid and continue to simmer on a low heat for around 3 hours until the juices reduce to a syrupy caramel, basting the pears from time to time.
Note: The pears can also be cooked in the oven on 150C/280F for 3 hours after the first hour on the stovetop.