1. Combine sugar, water, pumpkin puree, and pumpkin spice in a small saucepan. Bring to a boil and simmer for 3-5 minutes. Remove and place in heat-safe container. Chill until needed. Refrigerate up to 5 days.
2. In a mug, combine hot espresso and pumpkin spice sauce. Top with heated and frothed milk. Milk can be frothed by placing hot milk in frother machine, using hand-held frother or high-powered blender.
3. Add Creme Chantilly and dust with ground cinnamon.