This recipe is for a rich and bitter panna cotta made with black cocoa. Because it's set with sheet gelatin, it has a smooth, melt-in-your-mouth texture. The bittersweetness of the caramel and the depth of the black cocoa blend perfectly, creating a luxurious taste for adults. While it involves making the caramel over a flame and a heating process, it's easy to make by simply chilling it in the refrigerator until set, making it a perfect dessert for a home café or a special gift.