I love shortbread. I also love chocolate. Maida Heatter's Book of Great Chocolate Desserts provided what has become my favorite shortbread recipe. Chances are you have already have on hand everything you need to whip up a batch. She also says some of her friends like to add 1 teaspoon of dry instant espresso or other instant coffee (not granular). She also advises that you can omit the salt/vanilla! These are easy to make and have a nice strong chocolate flavor. The powdered sugar makes them tender and crumbly like Walkers or other Scottish shortbreads.