Inside job is troubling restaurant (6)
I believe the answer is:
bistro
'restaurant' is the definition.
(bistro is a kind of restaurant)
'inside job is troubling' is the wordplay.
'inside' indicates the answer is hidden within the clue.
'BISTRO' can be found hidden inside 'job is troubling'.
(Other definitions for bistro that I've seen before include "Coming out of restaurant" , "Orbits (anag)" , "Small informal french-style resturaunt" , "Small restaurant - robs it (anag)" , "Small informal French cafi" .)