Chop up the chocolate and melt in a bain-marie.
Let cool while stirring, warm again, and spread about 1mm thick on parchment paper.
After it hardens, cut into 2×2½ in (5×6 cm) diamonds (or squares) and place briefly in the refrigerator.
For the filling, melt the milk and dark chocolate in a bain-marie.
Beat the egg white and sugar.
Lightly beat the double cream and mix with the egg whites and warm chocolate.
For the sauce, put the mandarin juice in a pot, reduce to half, and bind with cornstarch.
Flavor with Armagnac and let cool.
Fill a piping bag with cream.
Remove the chocolate leaves from the parchment paper and layer 4 leaves per person with the cream.
Pour circles of sauce onto chilled placed, place the filled chocolate leaves on the sauce, and garnish with mandarin flowers and leaves.
