Cream the softened butter and brown sugar until smooth and slightly fluffy. Beat in the molasses, egg, and vanilla; the mixture may look a little separated, which is normal.

Whisk the flour, baking soda, salt, ginger, cinnamon, cloves, and optional nutmeg in a separate bowl. Add the dry mixture to the molasses mixture in batches, mixing only until a soft dough forms.

Divide the dough into two portions, flatten each into a disk, wrap, and chill for at least 1 hour. Chilling makes the dough easier to roll and helps reduce spreading.

Heat the oven to 350°F (175°C) and line baking sheets with parchment. Roll one dough disk on a lightly floured surface to approximately 1/4 inch (6 mm) thick, then cut into shapes.

Transfer the cookies to the prepared sheets, chilling the cut cookies briefly if the dough has become warm. Bake for 8–10 minutes, until the edges are set and the centers still look slightly soft.

Cool the cookies on the baking sheet for about 5 minutes, then transfer them to a rack and cool completely. Whisk the confectioners’ sugar, milk or cream, vanilla, and salt into a fairly thick glaze, then drizzle or spread it over the cooled cookies.