Preheat oven to 250°. In cup, dissolve instant coffee in boiling water; set aside. Melt over hot (not boiling) water, 1 cup semi-sweet chocolate morsels; stir in until smooth. Remove from heat; set aside. In large bowl, combine butter, confectioners? sugar and coffee; beat until smooth. Gradually blend in flour and salt. Stir in melted morsels. Roll dough between two pieces of waxed paper to 3/16-inch thickness. Remove top sheet; cut out cookies using 2 1/2-inch cookie cutter. Remove from waxed paper. and place on ungreased cookie sheets. Bake at 250° 25 minutes. Cool completely on wire racks. Melt over hot (not boiling) water, remaining 1 cup semi-sweet chocolate morsels; stir until smooth. Spread slightly rounded teaspoonful of melted chocolate on flat side of cookie; top with second cookie. Repeat with remaining cookies. Chill until set. Let stand at room temperature 15 minutes before serving.
Makes about 1 1/2 dozen 2 1/2-inch cookies.