1) Place the sugar, wine, water, cinnamon sticks, lemon zest and lemon juice in a medium pan. Peel the pears and, preferably using a melon baller, fully scoop out the core of each pear. Place the pears in the pan with the poaching liquid and cover with a lid, leaving a crack open. Poach until pears are just tender, about 10 minutes.
2) For the chocolate sauce, pour the water and sugar into a pan and bring to the boil. Reduce the heat and add the cocoa powder, continuously whisking for 4 to 5 minutes. Pour the liquid through a sieve into a bowl and store in the fridge.
To serve, remove the pears from the poaching liquid and arrange them in a serving dish with the cinnamon sticks. Pour over the chocolate sauce.