For a bit, Rachel's in Kigali, capital city (8)
I believe the answer is:
helsinki
'capital city' is the definition.
'for a bit rachel's in kigali' is the wordplay.
'for a bit' says the answer is hidden in the clue.
'HELSINKI' is hidden within 'rachels in kigali'.
(Other definitions for helsinki that I've seen before include "Main city of Finland" , "Finland's largest city" , "Sikh line (anag)" , "Is he link to a European city?" , "1952 Olympic Games venue" .)