Line a baking tray with baking parchment.
Add a little water (about 500 ml into a saucepan and add the almonds to it. Bring the water to a boil for no longer than 2 minutes. Then quickly strain the almonds. You will find that the skin just slips off the nuts. With a knife (now is the best time as they are softened) slice the almonds in half lengthwise. Spread them on a paper towel to dry.
50 g whole almonds
Separate the egg and place the egg yolk and egg white into separate bowls. Place the egg yolk in the fridge until needed.
1 egg
Sieve the icing /confections sugar to avoid any lumps. Roughly chop the marzipan in smaller pieces. Mix with the sugar, flour, ground almonds, egg white and orange liqueur and knead to a homogenous dough.
200 g marzipan, 80 g ground almonds, 1 egg, 80 g powdered sugar / icing sugar, 2 tablespoon flour
Next form the dough into an even roll and with a knife cut of equally size pieces. (I weighted them to ensure that they were equal and for me they were roughly 20 g each).
Form the dough pieces into balls and place them on the baking tray. (My balls had a rough 3 cm diameter)
Press three almond halves into each ball. (see picture)
Now mix the milk and egg yolks. Apply the egg wash with a pastry brush on the cookies. I like to also apply a further tablespoon or rosewater (affiliate link) or orange liquer onto the cookies before baking. 4 tablespoons milk, 1 tablespoon rosewater
Preheat your oven to 170°C or 338°F top to bottom heat and bake your cookies for approximately 15 minutes.
Leave to cool. If desired you can dust them with icing sugar before serving.