Cream butter and sugar with the whisk of the hand mixer. First stir in the eggs one by one, then add the syrup. Mix flour, baking powder, salt and spice and stir in slowly. Halve the dough. Wrap one half in foil and chill for about 1 hour. Stir cocoa into the other half. Wrap the dark dough in foil and put it in a cold place.
For the house templates, draw 3 different houses on cardboard (13-15 cm high, 6-9 cm wide) and cut them out. Cut the dark dough in half again. Roll out one half 2-3 mm thin on a floured work surface. Cut out houses from the dough using a small knife and the house templates (the dough softens very quickly. If the dough is much too soft, knead in some flour). Place houses on 3-4 baking trays covered with baking paper
For the city 6 light and dark houses are needed. Prick a hole in each of the remaining houses to hang them up. Knead the dough again and cut out some small squares and circles for doors and windows. Knead the dough again and chill. Process light-coloured dough in the same way
Brushing houses with some water. Stick windows and doors on the houses (light houses dark windows/doors, dark houses light windows/doors). Bake the trays one after the other in a preheated oven (electric cooker: 200 °C/ circulating air: 175 °C/ gas: level 3) for 7-8 minutes. Let the houses cool down on the trays first, then let them cool down on cake racks. Process both types of dough in the same way
Sieve the icing sugar into a bowl. Add the egg whites and mix with the whisk of the hand mixer to a smooth thick icing. Pour the icing into a piping bag or freezer bag and cut off a small corner. Decorate cooled gingerbread houses with icing and let dry for at least 30 minutes
Stick gingerbread houses with icing on a baking frame (approx. 23 x 23 cm) and let them dry. Fill the interior of the city as you wish, e.g. with Christmas balls or tissue paper
waiting time approx. 1 1/2 hours