Mix eggs, sugar and salt thoroughly in a saucepan.
Add honey and butter cut into pieces, place on the stove and heat (do not boil!) the mixture over a medium heat, stirring constantly, until the sugar and butter have dissolved.
Remove the honey mixture from the heat, add baking soda and stir thoroughly until the mixture foams properly.
Leave the honey mixture to cool to room temperature, stirring occasionally.
Now add flour to the honey mixture in batches and mix to form a very sticky dough.
Cover the dough airtight and refrigerate for at least 2 hours.
Divide the dough into two equal pieces and put one of them back in the fridge.
Divide the other piece of dough into two equal pieces again. First roll one piece of dough in flour and roll it out into a long rectangle or oval about 3 - 4 mm thick on a sheet of baking paper, cut out a number using the stencil and pierce it several times with a fork.
Place the baking paper with the number on a baking tray and bake in a preheated oven at 356 °F (180 °C) for approx. 4 - 5 minutes until lightly golden brown.
Carefully pull the baking paper with the baked number onto a flat surface and leave to cool.
Roll the second piece of dough in flour too, roll it out again on a sheet of baking paper and cut out the same number. Bake it in the same way as the first one and leave it to cool.
Now collect the leftover dough, roll it out, cut out the same number a third time and bake it.
Now take the second piece of dough out of the fridge and bake another number three times in the same way.
Make any cookies you like from the last pieces of dough. You can use these to decorate the number cake later.