Heat the heavy cream and espresso granules in a double boiler over medium heat. Once warmed, add the chocolate, stirring until completely melted and smooth. Remove from heat and cool slightly before transferring the mixture to the refrigerator. Chill until firm, about one hour. Once firm, use a melon baller or miniature scoop to portion out loosely rounded teaspoonfuls of chocolate onto a parchment-lined baking sheet. (They do not have to be perfectly round at this point, only equally portioned.) Return the chocolate to the refrigerator for a few minutes once all portions have been made: this allows mixture to firm up slightly. (Truffles can be made a day in advance up to this point and kept covered in the refrigerator. Bring to room temperature for 10 minutes before proceeding the next day.) While the truffles are chilling, line the desired toppings out in individual shallow dishes. Once you are ready to form the truffles, remove the portioned chocolate from the refrigerator and roll each between your palms to form a ball. (The surface will soften slightly when doing this, allowing the toppings to stick). Working with one at a time, coat each truffle in the desired topping and place back on parchment-lined surface. Store prepared truffles covered in the refrigerator or freezer. Bring to room temperature before serving.