Lustre dust is an edible dust that adds a shimmery look to a cake. It can be added to most frosting, including rolled fondant, and it comes in a wide variety of colours. Lustre dust is usually applied with a paint brush, a dusting brush or an airbrush gun. The airbrush gun works best for large cakes because it allows you to cover more space in less time.
Start with a cake that is already covered in rolled fondant.
Cover the area you are working in with old newspapers. Lustre dust tends to go everywhere, no matter how careful you are.
Pour 1/4 tsp of lustre dust into a small cup.
Add three drops of lemon extract into the cup.
Mix both ingredients together with a spoon.
Pour the mixture into the opening on top of your airbrush pen. You may not be able to pour the entire amount into the pen, but you can refill when it empties.
Turn on the compressor, which is the box connected to the airbrush pen. Make sure it's on the lowest setting. You can increase the air pressure later, but it's best to start with the lowest air pressure possible.
Aim the airbrush pen at the cake and hold it about 4 inches from the cake. Move the trigger located on top of the pen with your finger to start apply the lustre dust.
Start from the bottom of one side of the cake and move up. When you finish with one side, move the cake so that you can start on another side. Don't spend too long on one section. Move the pen quickly over each area. You can always go back and apply more.