Whisk flour, baking soda, salt, ginger, cinnamon, cloves, and nutmeg in a large bowl.
Beat butter and brown sugar until light and fluffy, about 2 minutes.
Mix in molasses, vanilla, and orange zest if using until smooth.
Add dry ingredients in two additions, mixing on low just to combine.
Drizzle in milk and mix briefly until a soft dough forms.
Divide dough, flatten into two disks, wrap, and chill 30 minutes.
Heat oven to 350°F. Line two baking sheets with parchment paper.
Roll one dough disk to 1/4 inch on a lightly floured surface.
Cut shapes and transfer to prepared sheets, spacing about 1 inch apart.
Sprinkle with coarse sugar for sparkle, if desired.
Bake 8–10 minutes, rotating pans halfway, until edges are set.
Cool 5 minutes on the sheet, then finish cooling on a wire rack.