Updated Nov 15, 2019Chatelaine
1. Whisk flours with zest, baking powder and salt in a medium bowl. Set aside.
2. Beat butter with sugar in a large bowl, using an electric mixer on medium-high, until fluffy, about 1 min. Beat in egg. Reduce speed to low and gradually beat in flour mixture, just until combined. Stir in cherries and chocolate, then gather into a ball. Divide dough in half, then roll each portion into a 2-in.-wide log. Wrap logs in plastic wrap and twist ends. Chill until firm, about 1 hr.
3. Position rack in centre of oven, then preheat to 325F. Line 2 baking sheets with parchment. Slice cookies into 1/2-in. thick rounds, then arrange 1 in. apart on prepared sheets.
4. Bake until cookies are golden around the edges, 19 to 20 min. Let cookies stand on sheets for 1 min, then transfer to a wire rack to cool completely. Repeat with remaining dough.
Maraschino cherries should be as dry as possible for crisp cookies. Drain in a sieve over a bowl in the refrigerator overnight. Squeeze dry on paper towels.
Cookies will keep well stored in an airtight container up to 3 days.