US: Usually, "scorched" would imply burning with an incredible amount of heat. If someone told me that something was "scorched" I would think that it was not just lightly burned, but really, really, really burned. Painfully burned. Destructively burned. If you said you had "scorched your dinner" last night, I would assume that you burned it so bad that you couldn't eat it. But, if you said "I had 'scorched rice' for dinner," I'd assume it was some kind of rice dish - because English is strange that way. You could also say "I had tahdig for dinner - it's a rice dish where you brown the rice," I would get a pretty decent idea of what you had actually eaten.

I would say generally speaking they mean basically the same thing, but there might more meaning behind it when it comes to cooking that I'm not aware of.

To 'scorch' in cooking means to burn slightly and superficially so as to affect color. If you say burnt rice it implies that it is inedible.

I've heard the rice in Tahdig described as "golden brown" or "caramelized". "Scortched" or "burnt" rice would be inedible.

Hi, this is one of those situations where it depends on the context of how the words are used. Scorched usually refers to something where just the surface has been burnt and it could be done either deliberately or not. Burnt is the more general word and often means that the damage done by heat is more substantial, covers more area or that it's not just on the surface and instead is deeper. To call something burnt usually implies a negative thing, but then you have foods such as burnt butter which is a specific technique that is wanted.