Part of me is inclined to agree with you. There’s nothing “wrong” with cassia. But it bothers me that we’ve established a precedent that we can just label one food as another because it’s cheaper and easier to access.
Cassia cinnamon
Ceylon cinnamon
The latter is what this article is calling "real" but they are both real. Ceylon originates in India and is used in Indian cooking. Cassia originates in SEA/China Asia and is used in recipes there.
They are simply two different varieties of the same tree and they are both cinnamon. In fact there are many more varieties than just that two, same as with apples, tea, coffee or any other plant and it makes no sense to designate only one variety of cinnamon as "real". They have different flavors and neither is better.
I have no real point here other than cinnamon (i.e. the genus Cinnamomum) is fascinating and confusing in equal measures and people should definitely read up on it.
As an Indian, I can assure you that the cinnamon we use in our cooking is indeed Cassia.
Ceylon is in Sri Lanka, a bit south of us.
Cassia does originally come from China though, although I guess it has spread a long way.
I hate it because we're often sold an inferior product and likewise it's probably too late to do anything about it.
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