yellow food colouring, add drops until you get the desired colour, same with the orange colouring
Instructions
Pre-heated oven 1800C, grease a 8”spring form tin, line with baking paper and lightly dust with flour
Cream butter and sugar till light and fluffy. Add eggs one at a time until combined. Add sifted dry ingredients and mix until all combined.
Split mix in half and add lemon rind and yellow food colouring and mix till all is combined. Repeat with the orange.
Put cake mix into 2 piping bags and pipe one colour on top of the other until all cake mix is used. Turn the tin in circles to distribute the mix evenly in the tin and cook for 45 minutes.
Notes
Swiss Meringue Buttercream follow the link to make this Swiss meringue buttercream, then split buttercream in half and add the food colouring to one half . Put coloured part on oneside and then the plain buttercream next to it in piping bag and decorate top.
Alternatively you can just make a plain icing or what ever topping you like.