Sort of coffee popular fellow initially took (7)
I believe the answer is:
instant
'sort of coffee' is the definition.
(I've seen this before)
'popular fellow initially took' is the wordplay.
'popular' becomes 'in' (something that's 'in' is fashionable).
'fellow' becomes 'stan' (man's name).
'initially' indicates taking the first letters.
The initial letter of 'took' is 't'.
'in'+'stan'+'t'='INSTANT'
(Other definitions for instant that I've seen before include "Immediate; moment in time" , "like some coffee?" , "Precise moment" , "Tick" , "Trice" .)