Preheat oven to 160C fan-forced.

Sift flour, baking powder and salt together. Beat butter and sugar together in a bowl or food processor. Add egg and vanilla and mix to combine. Gradually add dry ingredients and mix until combined. Shape into a disc, wrap in cling film and refrigerate for 30 minutes to rest and firm up the dough.

Lightly flour your work surface and roll out the dough thinly to about 1cm thickness. Cut out shapes and place on oven trays lined with baking paper. Sprinkle with a little extra sugar, if desired.

Bake in oven for 12 minutes until cooked and lightly browned. Remove from oven and allow to cool on trays.

To make icing, sift icing sugar and combine with egg white and lemon juice until you have the desired consistency. If the mixture is too runny, add extra icing sugar. Divide the mixture between smaller bowls and colour with your choice of food colouring. Use only a few drops of colouring.

Spoon coloured icing into zip-lock bags, close securely and snip a small hole in the bottom corner. Pipe designs onto the cooled bikkies.