Peel pears and leave stem intact. In a large saucepan, bring wine and an equal amount of cold water to a simmer. Split vanilla bean lengthwise and add to wine and water mixture. Add cinnamon sticks, bay leaves and sugar, to taste. Add pears to liquid and simmer for about 20 minutes or until tender. Cool pears in wine mixture to room temperature. You can refrigerate them in the poaching liquid until you're ready to fill them.
Remove stems from pears and set stems aside. Core pears with an apple corer, leaving pear whole.
Whisk together mascarpone cheese, heavy cream, pinch cinnamon and powdered sugar until smooth. Transfer to a pastry bag, or if you do not have one, use wax paper tightly wrapped into a cone with the corner snipped off. Pipe filling into cored pears and finish by putting the stems gently into the mascarpone filling on top of the pears.
Bring sauce up to a simmer and reduce by half. Add butter to reduced sauce and stir until combined. Spoon generously over pears. Cool to room temperature before serving.