I did a quick version of this using:
- 1 tablespoon premade pumpkin pie fillng
- 1 cup milk
- 1 tablespoon vanilla extract.
Add pumpkin pie filling to milk in a saucepan over medium heat. Whisk. Heat until steaming.
Remove from heat and add vanilla.
Add to coffee.
The original recipe is from http://www.thekitchn.com who uses pureed pumpkin as follows:
2 cups milk
2 tablespoons canned pumpkin (NOT pie filling)
2 tablespoons sugar or sugar substitute - you can halve this amount
2 tablespoons vanilla extract
1/2 teaspoon pumpkin pie spice (generally a mix of ginger, clove, nutmeg & cinnamon)
1-2 shots espresso (about 1/4 cup of espresso or 1/2 cup of strong brewed coffee if you don't have an espresso machine.)
In a saucepan combine milk, pumpkin and sugar and cook on medium heat, stirring, until steaming. Remove from heat, stir in vanilla and spice, transfer to a blender and process for 15 seconds until foamy. If you don't have a blender, don't worry about it - just whisk the mixture really well with a wire whisk.
Pour into a large mug or two mugs. Add the espresso on top.
Optional: Top with whipped cream and sprinkle pumpkin pie spice, nutmeg, or cinnamon on top.