Whisk together the pumpkin puree, milk, sugar, pumpkin pie spice, and vanilla.
To heat in the microwave, place in a microwave-safe container. Cover the container with plastic wrap but vent slightly on one side. Microwave for 1 to 2 minutes or until the milk is steaming.
To heat over the oven, place the mixture in a small saucepan and heat while stirring until steaming.
Remove from heat and whisk vigorously or use a milk frother until the milk is foamy.
Brew the coffee into a large mug.
Gently stir in the foamed pumpkin and milk mixture.
If desired, garnish the coffee with whipped cream and a dusting of pumpkin pie spice.