OK - can the brasserie finally produce a joint? (4)
I believe the answer is:
knee
'a joint?' is the definition.
(knee is a kind of joint)
'ok can the brasserie finally' is the wordplay.
'finally' indicates one should take the final letters.
The final letters of 'ok can the brasserie' are 'KNEE'.
'produce' acts as a link.
(Other definitions for knee that I've seen before include "Hinged joint" , "Hinge joint" , "may present problem to maid" , "Human joint" , "Major joint in leg" .)