Preheat the oven to 350°F (175°C) and line a muffin tin with paper liners.

In a bowl, whisk together the flour, baking soda, spices, and salt.

In a stand mixer, mix the melted butter, brown sugar, molasses, and the egg on medium-high until light and fluffy, scraping down the sides as needed.

Lower the mixer speed and gradually add the flour mixture, followed by the room-temperature water, mixing until just combined.

Fill muffin cups two-thirds full with batter.

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

Allow cupcakes to cool in the pan for 5 minutes before transferring them to a wire rack to cool completely.

In a mixer, combine the cream cheese and unsalted butter until smooth.

Add confectioners' sugar and cinnamon, mixing well.

Add vanilla and adjust consistency with milk as needed.

Pipe frosting onto cooled cupcakes and garnish with mini gingerbread men.