For once, I didn't change this recipe at all (except to add a little more ginger). According to the folks at Cooks Illustrated, from whence it came, it's best to use flour with a protein of around 10.5 percent (Pillsbury or Gold Medal) rather than something (like King Arthur at 11.7 percent). The higher protein will result in drier, cakier cookies.
Makes 2 dozen cookies
1/2 c sugar, for rolling dough
1 t grated fresh ginger (I use this stuff and press the liquid out in paper towels)
2 c unbleached all-purpose flour
1/2 t baking powder
1/4 t table salt
16 T (2 sticks) unsalted butter, softened but still firm (60 to 65 degrees F)
1 c granulated sugar
1 T light brown sugar
1 large egg
2-4 T minced crystallized ginger
1 1/2 t vanilla extract
In food processor or spice grinder, process 1/2 c sugar and fresh ginger until just combined; set aside for rolling.
Adjust oven racks to upper- and lower-middle positions; heat oven to 375 degrees. Line two large baking sheets with parchment paper. Whisk flour, baking powder, and salt in medium bowl; set aside.
With mixer, beat butter, 1 c sugar, and brown sugar at medium speed until light and fluffy, about 3 minutes, scraping down sides of bowl as needed. Add egg, crystallized ginger, and vanilla; beat at medium speed until combined, about 30 seconds. Add dry ingredients and beat at low speed until just combined, about 30 seconds.
Place ginger sugar for rolling in shallow bowl. Fill medium bowl with cold tap water. Dip hands in water and shake off the excess (this prevents dough from sticking to your hands and ensure that sugar sticks to dough). Roll heaping tablespoon dough into 1 1/2" ball between moistened palms; roll ball in ginger sugar, then place on prepared baking sheet. Repeat with remaining dough, moistening hands frequently and spacing balls about 2" apart. Butter the bottom of a flat-bottomed drinking glass; dip bottom of glass in remaining ginger sugar and flatten dough balls with bottom of glass until dough is 1/2-3/4" thick.
Bake until cookies are golden brown around edges and just set and very lightly colored in center, 15 to 18 minutes, reversing position of cookie sheets from front to back and top to bottom halfway through baking time. Cool cookies on baking sheet about 3 minutes; using wide metal spatula, transfer cookies to wire rack and cool to room temperature.