This came about when I had some sweetened mascarpone cheese leftover from a tart I made the previous week. This is by far the BEST cookie I have ever made. That means a lot considering I have made probably hundreds of different cookies. One bite and I was hooked. This is no humble cookie, it is elegant. I have served it at a dinner party with miniature vanilla shakes. Hope you enjoy! —singing_baker
Make espresso shortbread. Put butter and 1/4 cup sugar in a mixing bowl with the paddle attachment. Beat until fluffy. Slowly add in flour, espresso powder, salt and Vanilla. Shape dough into a disc, wrap in plastic and put in fridge for about an hour.
Preheat oven to 350 degrees. Roll out dough to a 1/8 inch thickness. Cut out rounds with a cookie or biscuit cutter no bigger than an inch and a half. put rounds in freezer until firm. Place on baking sheet and bake for about 10 minutes or until the edges start getting brown. Transfer to wire racks to cool completely.
Make Filling: Combine mascarpone cheese, remaining sugar and vanilla bean paste in a mixing bowl with the paddle attachment until just combined. Put mixture in a pastry bag with a large round tip. this just makes it easier to put on the cookie without breaking it.
To make cookies first put about a teaspoon of melted chocolate on one side and a decent piping of cheese on another and then sandwich them together. Enjoy!