Combine flour, butter, sugar and eggs and knead to a smooth dough. Chill for 1 hour in the fridge.
Preheat oven to 200 degrees C and line a baking tray with baking paper.
Roll out dough on a floured surface to 5mm thick. Cut out biscuits with bird shaped cutter. Place on baking sheet and bake 12-15 minutes, but don't let them get too dark. Let cool.
Mix icing sugar with lemon juice to make a thick icing. Add food colouring as desired. Use to ice biscuits and let set.