In a large bowl, whisk together flour, ginger, cloves, nutmeg, baking soda, baking powder, and salt; set aside. Using an electric mixer, beat butter and brown sugar until light and fluffy; beat in egg and molasses. With mixer on low, gradually add flour mixture; mix just until combined. Divide dough in half; flatten into disks. Wrap each in plastic, and refrigerate until firm, at least 2 hours and up to 2 days, or freeze up to 3 months (thaw before baking).
Preheat oven to 350 degrees, with racks set in upper and lower thirds. Working with one disk at a time, place dough on lightly floured parchment paper, and roll out to 1/8 inch thick, dusting lightly with flour as needed. Using paper, lift dough onto two baking sheets; freeze until firm, about 20 minutes.
Remove paper and dough from baking sheets. Using a long offset spatula, loosen dough from paper. Cut out shapes with cookie cutters, and brush off any excess flour. Transfer to baking sheets. (Gather scraps, briefly freeze, and re-roll.)
For softer cookies, bake 8 to 10 minutes; for crunchier cookies, bake 11 to 12 minutes, rotating sheets halfway through. Transfer cookies to a wire rack to cool completely.
Make icing: In a large bowl, whisk together confectioners' sugar, powdered egg whites, and 1/4 cup water (if needed, adjust consistency with confectioners' sugar). Transfer icing to a pastry bag with a small tip, or place in a resealable plastic bag, and snip a small hole in one corner. Decorate cookies as desired.
Make sure the disks of dough are well-chilled so they're easy to roll out thin. Roll from the center out, and aim for an even thickness, stopping just short of the edge of the dough. A quick dip in flour will keep the cookie cutter from sticking to the dough. Look for powdered egg whites in the baking aisle at your supermarket.