Bar ribs to be served (6)
I believe the answer is:
bistro
'bar' is the definition.
(I have seen 'French bar' mean 'bistro' so perhaps 'bar' could also mean 'bistro')
'ribs to be served' is the wordplay.
'be served' indicates an anagram.
'ribs'+'to'='ribsto'
'ribsto' with letters rearranged gives 'BISTRO'.
(Other definitions for bistro that I've seen before include "'Small, inexpensive restaurant (6)'" , "Small informal french-style resturaunt" , "Cafe bar" , "Small informal French restaurant" , "somewhere to eat" .)