Find an image you want to use (Make an inverted copy). Leave the butter at room temperature.

Put the butter in a bowl and beat until creamy consistency. Add sugar little by little and whisk well until pale and fluffy.

Stir in a beaten egg little by little (add in 3-5 portions) and whisk well.

Put the flour and baking powder together and add to the mixture. Replace the whisk for a plastic spatula and stir briskly with a cutting motion.

Flatten the dough and wrap in cling film. Leave to rest in the fridge for more than 1 hour.

Chop the chocolate with a knife and melt in a bain marie.

Place a piece of baking paper on the prepared picture at Step 1 and secure with tape. Trace the picture with a cocktail stick with melted chocolate at Step 6.

Follow the hints and you will have better results. When the chocolate starts to harden, melt in a bain marie again.

After drawing, remove the original picture and chill the baking paper in the fridge for more than 10 minutes.

Taking out Step 5 from the fridge and lay on baking paper. Roll out the dough over the paper with a rolling pin. Put chopsticks at both sides of the dough, so that the thickness will be even.

Put Step 9 with the chocolate on Step 10. Roll out with a rolling pin. Put in the fridge and leave to rest for 5-10 minutes.

Take out Step 11 from the fridge and peel off the baking paper slowly. Lift up the corner of the paper and peel off slowly. When you're having difficulty, check Step 15.

Bake in pre-heated oven to 355°F/180°C for about 7-8 minutes.

Done! When the edges has browned nicely, it is ready to take out of the oven.