Strongly brew a cup of coffee. While still hot, mix in the sugar. Drop in the cinnamon stick and allow to steep for 1 hour. Remove the cinnamon stick and allow the infused coffee to cool completely.
In a large mixing bowl, beat together the vanilla pudding mix & cold milk. Then beat in the mascarpone cheese until smooth & creamy. Fold in the whipped topping & ground cinnamon. Set aside.
Arrange half of the ladyfingers in the bottom of a 9x9 inch baking pan. Brush the ladyfingers with about half of the cooled cinnamon coffee.
Spread half of the pudding/mascarpone cheese mixture over the ladyfingers in the dish. Cover with the remaining ladyfingers; then brush the second layer of ladyfingers with the remaining coffee mixture. Top with the remaining pudding/mascarpone cheese mixture.
Cover & refrigerate for at least 4 hours & up to overnight. Top with a little whipped topping & a sprinkle of ground cinnamon before serving, if desired. Enjoy immediately. You can cover & refrigerate any leftovers for up to 3 days.