To prepare bread pudding, preheat oven to 350 degrees. Whisk together half and half, pumpkin pie filling, brown sugar, eggs and vanilla. Fold in bread cubes. Add cranberries if desired. Spray baking dish with non-stick cooking spray or grease dish with butter. Pour mixture in prepared baking dish. Allow to set for 15 minutes. Bake for 40 minutes, or until tester comes out clean when inserted in the center of the dish.
Stir together the brown sugar and butter in a heavy medium saucepan over medium heat until butter is melted. Whisk in cream and stir until sauce is smooth and sugar is dissolved, about 5 minutes.
Serve bread pudding warm with caramel sauce on the side or drizzled overtop.