'Choc ice' is used as an insult.

'Choc ice' means 'black on the outsie, white on the inside'.

In order for 'coc-ice' to be an insult, part of 'black on the outside, white on the inside' must be pejorative.

Clearly that part is 'white on the inside', since 'black on the outside' is a statement of plain fact.

In this case 'white' is being used as an insult, so, by implication, 'white' must be inferior to black, or at least somehow bad.

The ranking of people by their skin colour is the very definition of racism.

Let's have no more cock about 'choc-ice' not being racist.