1. Whisk the flour, cardamom, and salt in a bowl.
2. Put the butter & confectioners' sugar in a food processor, and process until smooth.
Pulse in the egg, vanilla, and lemon zest until combined
3. Add the flour mixture and process to make a soft buttery dough.
4. Divide enough dough in half into 2 (12 inch long) sheets of plastic wrap, using the plastic, shape into rough logs.
5. Refridgerate the dough logs for 30 mins until just firm enough to shape into uniform logs, 8 inches long by 2 inches in diameter.
Refridgerate until firm, at least 2 hrs or overnight.
6. Scatter the sanding sugars (or other decorating items) on a work surface and roll the logs until completely coated.
7. Cut into 1/4 inch thick cookies and space about 1 inch apart on parchment-lined baking sheets.
8. Bake until golden around edges, about 20 - 30 mins. Cool cookies on the pan on wire racks. Store in airtight container at room temp for up to 2 weeks.
