Grate marzipan. Knead 275 g flour, sugar, marzipan, orange peel, speculoos spice, butter in flakes and egg first with the dough hooks of the mixer, then with your hands to a smooth dough.
Wrap dough in foil and chill for about 1 hour.
Line two baking trays with baking paper and sprinkle with almonds. Beat the egg whites until stiff, while sprinkling 100 g icing sugar.
Roll out the dough 2-3 mm thinly on a little flour. Cut out approx. 35 hearts with two heart-shaped cutters of different sizes (approx. 5.5 and 7 cm high). Knead the dough again and again and roll out again.
Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer). Spread hearts on the baking trays, press lightly on the almonds. Prick holes with a wooden skewer to hang them up.
Coat half of the hearts with cast iron. Bake all cookies in a hot oven for 12-14 minutes. Let them cool down. If necessary, dust with 1 teaspoon of icing sugar and decorate with pretty gift ribbons as pendants.