Heat oven to 180C/160C fan/gas 4 and prepare two lined baking trays. Beat the butter and sugar together until combined then beat in the egg and vanilla. Add all of the flour and mix into a soft dough. If the dough is very soft, chill for 15 mins before shaping. You can freeze the cookie dough for a later date, but defrost thoroughly before baking.
Roll the dough into log shapes about 1.5cm-2cm in diameter, then cut into pieces 15cm long (using the ruler to measure).
Insert a soaked lolly stick into each biscuit as well as a piece of Mikado for an arm on each side. Place on the baking trays evenly spread apart.
Bake for 15-20 min until golden brown, but do check after 15 mins as all ovens vary. Transfer onto a wire rack to cool.
Break the milk chocolate into pieces and melt in a bowl set over gently simmering water, or in short bursts in the microwave. Once the biscuits are cool, use a pastry brush to gently paint the chocolate all over the back of each stick, going a little around the sides and on the back of the Mikados.
Once set, flip the sticks over and paint the fronts, then leave for 30 mins to completely set.
Mould little pieces of the icing to create his leafy coif, goggle eyes and mouth. Stick them on using a little of the leftover melted chocolate.