*Preheat oven to 350 degrees. Have ready 2 baking sheets.
*Roll teaspoonfuls of the dough into balls and arrange on the baking sheets.
*Bake the cookies until firm but not browned, 10-12 minutes. Transfer to wire racks to cool completely.
*While the cookies are cooking combine the chocolate and the remaining 2 TBS butter in the top pan of a double boiler or in a heatproof bowl. Set over simmering water and heat until the chocolate softens. Remove from the heat and stir until the chocolate is smooth. Let cool slightly.
*Using a butter knife, spread a small amount of the chocolate on the bottom of a cookie. Place the bottom of a second cookie on the chocolate and press together. Repeat with the remaining cookies. Let cool on the wire racks until the filling is set.