The pizza thing seemed incredibly silly to me. Surely the restaurant has already paid the tax when they bought the raw ingredients? Must any product served in a restaurant be taxed according to the rate of the most highly taxed ingredient in it, regardless of proportion?

So I looked it up. And yes, that is exactly the case, and it's an absurd situation that is causing massive headaches.

https://www.bbc.co.uk/news/world-asia-india-63281037