Step 1: In a large bowl, cream together the softened unsalted butter and packed light brown sugar until light and fluffy.
Step 2: Beat in the large egg, then stir in the molasses, apple cider vinegar, and vanilla extract until well combined.
Step 3: In a separate medium bowl, whisk together the all-purpose flour, baking soda, salt, ground ginger, ground cinnamon, ground allspice, ground cloves, and ground nutmeg.
Step 4: Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined and a soft dough forms. Do not overmix.
Step 5: Divide the dough into two equal portions, flatten each into a disk, wrap tightly in plastic wrap, and refrigerate for at least 2 hours (or up to 3 days). This is crucial for preventing spread and deepening flavors.
Step 6: Preheat your oven to 350°F (175°C) and line baking sheets with parchment paper. On a lightly floured surface, roll out one disk of chilled dough to about ¼-inch thickness.
Step 7: Use your favorite cookie cutters to cut out shapes. Carefully transfer the cut-out cookies to the prepared baking sheets, leaving about 1 inch between them. Gather and re-roll scraps once.
Step 8: Bake for 8-10 minutes, or until the edges are just set and slightly darker, but the centers are still soft. Baking time will vary based on cookie size and oven.
Step 9: Let the cookies cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.
Step 10: Once completely cool, decorate with royal icing or your favorite frosting, if desired.