Add the cranberry juice, orange peel, cinnamon sticks, and ginger to the crockpot. Place the whole, peeled pears in the crockpot. Pears will float and can be turned periodically during cooking. Cook on low setting for 3 to 4 hours.
Place the arrowroot or cornstarch in a bowl, and gradually whisk in 1/2 cup of the poaching liquid. Strain over the pot to remove the cinnamon sticks, ginger, star anise, orange peels, and raisins. Reserve the plumped raisins for serving.
Heat the liquid over high heat, and pour in the arrowroot or cornstarch slurry. Bring to a boil and then reduce heat and cook for 5 minutes, or until a syrupy consistency is achieved.
Let cool for a bit. Pour the cranberry syrup over the top of the poached pears, add in the plumped raisins, and add a dollop of whipped cream or vanilla frozen yogurt to serve. Garnish with mint leaves if desired.