Sorry to jump in, I'm not Minang so I can't say much. This is just what I know from reading somewhere.
So
@Indos , CMIIW on this.
Minang has this ancient literature called
Tambo Alam. It tells story about the ancestor of the Minangkabau people, an ancient king name Maharaja Diraja. The king has four (according to one version) formidable bodyguards, one of them is "Harimau Campo" (Tiger from Champa). In other version, Harimau Campo is a maid who became adoptive daughter of the king.
Harimau Champa is believed to be the ancestor of Luhak Agam Minangkabau people.
There are also close similarities between pattern carved on the walls of My Son temple in Vietnam and the ones commonly used in Minang traditional house - Rumah Gadang.
That's what I've been reading.
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Bro Indos, I also think Minang has some connection with Koreans.. My conjecture is based on some term used in both ethnic.
Older male/brother > Korea
Oppa , Minang
Uda
Older female/sister > Korea
Unni , Minang
Uni
And, in Tambo Alam, it says that Maharaja Diraja has an older brother who went to East Asia and ruled there. He probably the ancestor of Koreans if the myth is true.. hehe
I've actually read another article that said these weasel coffee are dangerous for the human consumption and it's marketing gimmick that is driving the prices up for a few unlucky vietnamese with more money than cents (sense). This will never pass stricter western quality control as I've yet to see them in Canada and US.
It has gained popularity in US for quite some time and readily available.
Even featured in a movie called Bucket List where Jack Nicholson drinks it ..
.