Pour ½ grated chocolate tablet into a saucepan, add 3 spoons cream, and place on top of the stove. Stir until the chocolate dissolves, then remove from the heat. Beat 3–4 egg yolks with sugar until white, mix with the chocolate and ½ glass cream, and stir over the fire until it thickens. Remove and cool, beating constantly with a whisk over ice. Separately whip 1½ glasses cream and fold into the chocolate mixture. Add ½ glass isinglass, pile into a mold, and set on ice.