Combine the pears, sugar, cinnamon sticks, whole cloves, vanilla pod and allspice in a large stock pot and cover with water. You want the water to be about 2 inches higher than the pears. Bring the mixture to a boil, reduce it to a simmer and cook for 1 hour uncovered. After 1 hour, you can mash some of the pears (they will just fall apart). Cover the pot and simmer for another 2 hours.
After 2 hours, let the mixture cool slightly. Strain it through a fine mesh sieve (I did so twice) to remove the solids. Some of the solids may remain. You can strain it through cheesecloth one more time before serving if desired. Serve hot with cinnamon sticks!