Mix flour, sugar and salt in a bowl. Add egg and butter in pieces. Knead first with the dough hooks of the hand mixer, then with your hands to a smooth dough. Wrap the dough in foil and chill for about 45 minutes
Roll out the dough on a floured work surface to a thickness of approx. 4 mm. Cut out approx. 20 small circles (6.5 cm Ø) and 20 large circles (7 cm Ø), cutting off approx. 1/3 of the large circles. In between knead the dough sections and rest of the dough again and again, roll out and cut out ebneso. Place the cookies on 2 baking trays lined with baking paper. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) one after the other for about 15 minutes. Remove the cookies and let them cool down on a cake rack
Colour half of the marzipan green. Colour 1/3 of the remaining marzipan red. Roll out the green marzipan with some icing sugar and cut out or cut out fir trees (2-2.5 cm high) as desired. Form small, thin rolls from the red marzipan. Roll out the rest of the marzipan with a little icing sugar and cut out or cut out mounds or snowmen (2 small circles) as desired. Cover marzipan with foil
Sieve the icing sugar into a bowl and mix with 4 tablespoons of water and lemon juice to a glaze. Colour half of the icing blue. Cover white icing with foil airtight. Spread the blue icing evenly on the cut cookies with a brush and decorate immediately with the marzipan and sugar stars (only 1 cookie at a time, the icing will set very quickly). Let the cookies dry for about 1 hour
Chop the chocolate and melt over a warm water bath. Put the chocolate in a freezer bag, cut off a small corner and decorate the snowmen with it. Spread white icing generously as strips on the large biscuits and press the decorated biscuits onto the icing with the cut surface facing down. Leave to dry again for about 1 hour
waiting time approx. 2 hours