Place the chocolate chips, salt, sugar, and espresso powder in a blender or food processor and pulse until finely ground., Add the egg and pulse just until everything is well combined; the mixture may start to form a cohesive mass., Heat the cream in a bowl in the microwave, or in a pan set over medium-high heat. Heat until the cream’s just short of a full rolling boil; it should be bubbling vigorously around the edges, with larger bubbles rippling across the interior. The temperature should be at least 205°F., Turn on the blender or processor, and slowly add the cream. Scrape down the sides of the container if necessary. Add the flavoring of your choice and pulse to blend., Divide into 6 individual serving cups. Cover with plastic wrap and refrigerate until firm, at least 2 hours., Serve with whipped cream, if desired. Or simply garnish with a sprinkle of confectioners' sugar and fresh berries.