Preheat the oven to 350°F (175°C). Line two baking sheets with parchment paper.
In a large bowl, cream together the softened butter and light brown sugar until light and fluffy, about 3 minutes.
Beat in the egg, then add the molasses and vanilla extract, mixing until well combined.
In a separate bowl, whisk together the all-purpose flour, baking soda, salt, ground ginger, ground cinnamon, ground cloves, and ground nutmeg.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Stir in the rolled oats until evenly distributed throughout the dough.
Divide the dough into two equal portions. On a lightly floured surface, roll each portion to about 1/4-inch thickness.
Use a gingerbread girl-shaped cookie cutter to cut out cookies and place them about 2 inches apart on the prepared baking sheets.
Gather the scraps, re-roll, and cut out additional cookies until all dough is used.
Bake in the preheated oven for 10 to 12 minutes, or until the edges are set and lightly browned.
Remove from the oven and allow the cookies to cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.