Cut out 16 squares of aluminum foil measuring 6½ inches (16.2 cm). Set a cake ring, 3 inches (7.5 cm) in diameter and 2 inches (5 cm) tall in the center of each square. Fold and pleat the edges of the foil up around the rings to make a tight seal. Because the cakes will be baked in a water bath, be certain that the foil reaches at least three-quarters of the way up the side of the rings. Brush melted butter inside the rings and over the bottom of the foil inside. Place the foil-covered rings on an even sheet pan or inside flat, even hotel pans. Set aside. To use a Flexipan, see “Directions for Using a Flexipan.”
Cut the unsweetened and sweet chocolate into small pieces. In an oversized pan, bring the crème de menthe, water, and 8ounces (225g) sugar to the scalding point. Remove from the heat and stir in the chocolate, mixing until all of the pieces are melted and thoroughly incorporated. Gradually add the butter, stirring until completely smooth. Set aside at room temperature.
Whip the eggs and the remaining 4ounces (115g) sugar at high speed until light and fluffy, about 3 minutes. Do not incorporate too much air or the finished cakes will be crumbly and difficult to work with. Gently fold the melted chocolate mixture into the egg mixture. Fold in the ground almonds.
Pour the batter into the prepared cake rings, dividing it evenly among them. Pour enough hot water into the pan around the rings to reach about ½ inch (6 mm) up the sides.
Bake immediately at 350°F(175°C) for approximately 30 minutes or until the tops of the cakes feel firm. Allow to cool slightly then refrigerate for at least 1 hour or, preferably, overnight before glazing.