• Position an oven rack in the center of the oven and preheat the oven to 350F degrees. Line the cookie sheets with silicone mats or spray them with nonstick cooking spray.
• In a large mixing bowl, mix together the Kahlua and coffee powder until dissolved. Add the brownie mix, melted butter, and egg and stir with a wooden spoon until the dry ingredients are just moistened and everything is well blended. Stir in the white chocolate chunks.
• Drop the dough by teaspoonfuls, 2 inches apart, onto the prepared cookie sheets.
• Bake one cookie sheet at a time in the center of the oven until the edges are set and the center is just barely set when lightly touched, 10 to 13 minutes.
• Remove from the oven and allow the cookies to cool for about 1 minute on the cookie sheets and then transfer the with a spatula to wire racks to cool completely.
• Repeat with remaining cookie dough, being sure that your cookie sheets are completely cooled before using them. (I sometimes run the backs of the cookie sheets under cold water to speed up the process.)

Make the Kahlua Icing:

• In a small bowl, combine the coffee liqueur, espresso powder, water, vanilla, and pinch of salt in a medium bowl until dissolved.
• Whisk in the powdered sugar until smooth. Add more water a little at a time, if necessary, to achieve a nice drizzling consistency.
• When the cookies are completely cool drizzle them with a little Kahlua icing.
• Makes 48 cookies.