Make the pumpkin puree in advance by dicing the piece and roasting for about half an hour in a preheated oven at 200 degrees.
Puree with a hand blender or blender and sieve the mixture so that you get a fine, slightly thin puree.
Then mix the cinnamon, ground ginger, ground cloves and ground nutmeg.
Heat the milk together with two tablespoons of puree and the Tagatesse over medium heat. Heat while stirring until it almost boils, but just before it does. Remove the pan from the heat and stir in the vanilla and 1 tsp of the homemade spice mixture.
Pour the mixture into a blender and blend at the highest setting. This makes the milk nice and airy and spread over two mugs.
Pour the coffee from the side to keep the milk nice and airy.