I have also had something similar. Chicken curry could relate to about 90% of the world.
My experience was from 'the other side'. I defended a child who was called racist because he argued with my child, (both were around 8 yrs old), over who would be 'black sonic', a cartoon character.
My son and his best friend were separated for over a week, I had to explain the script of a cartoon, and their friendship was never the same.
It was so pathetic to bring me in from work, I initially laughed when they told me, but this was the height of PC.
I will never forget taking my toddler to playgroup and being asked if it was OK to sing 'baa baa black sheep', I never went back again as I was so embarrassed.
I almost wish I'd said no, just to see the reaction.
Anyway, OP, I would speak to the other childs parents. No offence, none taken. If they could speak to the school stating that it would be beneficial.
I know I had to fight really hard to insist Ds friend wasn't being racist and they didn't log it. It turned into a massive thing, where a mixed race mother, with a mixed race child said no racism, but a caucasian teacher insisted it was against a 'black' child. I swear they must get paid extra because I fumed that my son was mixed race, not black and that I'd disputed it.
Eventually it was dropped.