Preheat your oven to 350°F (175°C) and line a cupcake tin with nine cupcake liners.

In a large bowl, whisk together sweet potato puree, water or milk, vanilla extract, vinegar, and oil if using. Let sit for 10 minutes.

In a separate bowl, sift or mix flour, sugar, cinnamon, salt, baking soda, and baking powder along with ground ginger if using.

Gently stir the dry ingredients into the wet mixture until just combined, avoiding overmixing.

Fill each cupcake liner about two-thirds full with batter.

Bake for approximately 18 minutes, or until a toothpick inserted in the center comes out clean.

Let the cupcakes cool in the tin for about 10 minutes, then transfer to a wire rack to cool completely.

Spread or pipe marshmallow fluff over each cooled cupcake, or use cream cheese if desired.