This is a slightly modified recipe from 'Chocolates and Confections' by Peter Greweling. As far as chocolate confections go, this is middle-of-the-road: slightly challenging, and somewhat time consuming. The resulting chocolates are tasty, but not in-your-face. The flavors unravel as you chew, and thereafter.
Marzipan:
215 g Blanched Almonds
215 g Blanched Hazelnuts
340 g Sugar
110 g Glucose Syrup
120 g Water
1) Plunge the almonds into boiling water. Return to a boil. Cover, remove from heat, and allow to soak for 5 minutes. Drain the nuts.
2) Coarsely grind the nuts in a food processor.
3) Combine the sugar, glucose syrup, and water. Cook to 115C. [Stir constantly until it boils, but then do not stir at all.]
4) Pour the hot syrup over the chopped nuts in a stainless-steel bowl. Mix together lightly.
5) Pour the syrup-coated nuts onto an oiled marble slab. Allow to cool to room temperature.
6) Grind half of the batch at a time in a food processor until it reaches the desired fine consistency. (This may take 10 minutes or more.) If the marzipan separates during the grinding process, add a small quantity of liquid such as spirit or boiled syrup, to restore the emulsion. [I added almond extract and a pinch of salt during the grinding process.]
7) Combine the ground batches of marzipan. Allow to cool to room temperature, roll, and use as desired. (Marzipan may be made up days in advance if desired.) [At this point, I placed the marzipan into a parchment-lined 8" x 8" x 2" pan and flattened it out with my knuckles.]
Chocolates:
300 g Dark Chocolate, melted and tempered
80 to 100 Hazelnuts, toasted
800 g Milk Chocolate, melted and tempered
8) Coat the marzipan with the 300 g of tempered dark chocolate.
9) Before the chocolate layer sets, quickly place the toasted hazelnuts on top, in a grid.
10) When the chocolate is partially set, cut the slab into squares.
11) Coat the squares in the tempered milk chocolate.