I don’t know how to get rid of the burnt smell/taste. But to your comment on burnt kheer, to avoid kheer burning/sticking to the pot, coat the pot with some butter - this prevents it from sticking to pot (this is in addition to the butter you add to the milk while cooking it).
While you still have to stir it constantly while cooking/reducing the milk down, the butter significantly reduces the milk boiling and burning into the pot.