1 x vanilla cake mix packet made to directions on the back of the packet. (The mix I used was 340gram home brand mix).
To make vanilla with chocolate swirls :-
Mix together in a medium bowl 1 x tablespoon unsweetened cocoa and 1x tablespoon caster sugar mixed with 3-4 tablespoons of milk. Add half the mixed vanilla cake to the chocolate keeping the other half vanilla. Alternate pouring and swirl of the colours into cupcake/muffin pans and bake as per usual about 15mins at 175*C.
To make vanilla with a coloured swirl just divide the mix into 2 bowls and have vanilla and green or vanilla and pink or vanilla and ….
This is a quick and easy way to make some 2 flavoured cupcakes out of the 1 flavoured vanilla packet/box mix.