Preheat oven to 180°C/ 350°F/ gas mark 4. Line a baking tray parchment paper.
Beat the butter and sugar together until it is fluffy. You can use a hand held blender if you have one.
Add the egg yolk and combine.
When it is well mixed, slowly add the flour, bicarbonate of soda and ginger.
Dust a clean surface with the flour and turn out the dough. Knead until smooth and chill in the fridge for 60 minutes.
Roll out the dough onto a floured surface until it is about ½ inch thick.
Press your gingerbread cutter into the dough.
Place on the baking tray leaving space between each biscuit to spread.
Bake in the oven for 10 minutes until golden.
Remove and leave to cool on a wire rack.
While the biscuits are cooling, mix the icing with the water.
Use the icing to raw a face onto the gingerbread men.
Decorate with the sweets if using.