Norbert said

<<<
You have a colon in the name of the header. I?m not sure zinc removes it. It could be a problem.

>>>

Ah, spot on. Apparently, we need the colon for Curl, but not for Pharo.�� Also, response setAuthorization turned out to be the best approach. For anyone searching this list, in the future,�� for Asana connectivity, my PoC is:

tmp1 := ZnClient new.
tmp1 request setAuthorization: 'Bearer <put your personal access token here>';��
url: 'https://app.asana.com/api/1.0/users/me'.
tmpJSON := NeoJSONReader fromString: tmp1 get.