Make the cookie base recipe. Form the dough into teaspoon-size balls.
Spread the coconut on a plate. Roll each ball in the coconut, pressing so it adheres. Place on prepared baking sheets. Bake for 10 to 12 minutes. Cool on the baking sheets for 5 minutes. Transfer the cookies to wire racks.
Meanwhile, in a heatproof bowl placed over, but not touching, simmering water, melt the white chocolate. Turn half the cookies upside down and spread the flat sides with the white chocolate. Sandwich them with the remaining cookies.
To Make Now and Bake Later: When you mix a batch of cookies, double the recipe. Bake half the dough according to the recipe and divide the rest into 4 equal portions. Roll each portion into a log about 1 1/2 inches in diameter. Wrap each log in plastic, then place in a resealable plastic bag. To save yourself time and hassle, label the bag with the flavor, the oven temperature, and the baking time, adding 3 to 6 minutes to the regular oven time. Freeze the dough for up to 3 months. To bake, slice the frozen dough into rounds about 1/2 inch thick, making as few or as many as you would like. Bake on a parchment- or foil-lined baking sheet.