Preheat oven at 170°C.

Cream butter & sugar together until fluffy. Next, add in egg gradually into the butter mixture.

Add in the rest of the dry ingredients and mix evenly.

Next, divide the dough into 3 parts and mix each of the dough with each of the colourings.

Add the 3 coloured dough into a prepared piping bag with nozzle.Pipe desired size on the baking tray.

Put the chocolate chip in the middle of the piped dough and bake at 170°C for 18-25 mins.