Heat the oven to 220ºC . Drain the pears, reserving the syrup. Combine the sugar, cornstarch and cinnamon in a saucepan and add the syrup and lemon juice. Heat until the syrup thickens then boil for 1 minute. Remove the pan from the heat and add the pears. Spoon the pears and the syrup into a 23 cm square baking pan. Combine the flour, sugar, baking powder, salt and cheddar, mixing well. Add the butter and milk, mixing until well blended. Spoon the dough over the pears, then bake for 25 to 30 minutes in the preheated oven. Serve hot with Vanilla Ice Cream or Whipped Cream.