I have a handful of favorite holiday confections that I make every year, but I’m always looking for something new and different. This is that cookie for me – born out of my love for buttery shortbread and a curiosity about how cherry, cardamom, and pistachio would get along in cookie form. Turns out they’re a smashing trio, with the orange zest adding brightness and the brown sugar a lovely caramel note, making me wonder why I haven’t always been making shortbread with brown sugar. I used the Cranberry-Pistachio Icebox Cookies from Gourmet as my jumping off point and made a lot of changes along the way. These cookies are incredibly, amazingly delicious with a cup of strong coffee. And even though they're perfect for the holidays, they can and should be made all year long.
Whisk together flour, ground cardamom, and kosher salt in a bowl. Set aside.
In the bowl of an electric mixer fitted with the paddle attachment, beat together butter, brown sugar and orange zest at medium speed until well blended, about 2 minutes -- stopping a few times to scrape the sides and bottom of the bowl with a rubber spatula. The mixture should be smooth and velvety, not fluffy. Overbeating the batter will incorporate too much air, causing the cookies to spread when baked.
Reduce speed to low and add the flour mixture in 3 batches, mixing just until dough comes together in clumps (stopping and scraping the bowl a few times with your rubber spatula), then mix in cherries and pistachios. You want all of the ingredients to be integrated without overworking / overmixing the dough.
Gather and press dough together, then divide into 2 equal pieces. Form each piece into a log about 1.5-inches in diameter, using plastic wrap as an aid. (If you want rectangular instead of circular cookies, square off long sides of each log). Tightly wrap each log in plastic wrap, then chill in the refrigerator until very firm, at least 2 hours. (Dough can be refrigerated up to 3 days or frozen for a month; if freezing, wrap the logs first in plastic wrap, then in foil -- or place in a freezer bag. Thaw in refrigerator before using.)
Heat oven to 350 degrees F. Line 2 large baking sheets with parchment paper.
Brush egg white evenly over each log, avoiding the ends. On a separate piece of parchment or wax paper, sprinkle coarse sugar and press bars into the sugar, turning to coat well and evenly, avoiding the ends. Cut each log crosswise into ¼-inch slices. If dough gets sticky or too soft, return to refrigerator until firm. Arrange cookies 1-inch apart on lined baking sheets.
Bake cookies, switching position of sheets halfway through baking, about 14 to 18 minutes, or until light golden; start checking doneness at 13 minutes; be careful not to overbake. When done, remove the baking sheets from the oven and transfer the cookies to cooling racks. I like to do this by keeping the cookies on the parchment, and sliding the parchment onto the cooling rack. (A little trick if your cookies have spread and lost their defined shapes: take the flat edge of a table knife, cookie spatula, or the curved back of a spoon and reshape the dough while it's still hot.) Cool completely. Stored in an airtight container, the cookies will keep for about a week. Like any shortbread, they improve with a little age.