In a large microwave-safe mug, combine all ingredients. Mix thoroughly with a small whisk until batter is smooth. Cook in the microwave at full power for about 2 minutes.
Allow cake to cool a few minutes before eating. The cake is not overly sweet so you can drizzle with melted Nutella spread if desired.
Notes
Both canned pumpkin puree and pumpkin pie filling are sold in the baking aisle and it’s important not to confuse them. Pumpkin pie filling is a short-cut product for making pumpkin pie and includes different spices and sweeteners. Pumpkin puree is just plain cooked pumpkin that has been pureed. So be sure to check the labels when you buy yours!
The nutrition information provided are only estimates based on an online nutritional calculator. This is not a comprehensive list of all the nutrients in the recipe (i.e., does not include vitamins, cholesterol, etc). I am not a certified nutritionist. Please consult a nutritionist or doctor for accurate information and any dietary restrictions and concerns you may have.