Rock found in ideal pudding served up in restaurant (9)
I believe the answer is:
trattoria
'restaurant' is the definition.
(I've seen this before)
'rock found in ideal pudding served up' is the wordplay.
'rock' becomes 'tor' (tor is a kind of rock**).
'found in' is an insertion indicator.
'ideal' becomes 'ai' (resembles 'At', slang for excellent).
'pudding' becomes 'tart'.
'served up' is a reversal indicator.
'ai'+'tart'='aitart'
'aitart' in reverse letter order is 'tratia'.
'tor' put into 'tratia' is 'TRATTORIA'.
'in' acts as a link.
(Other definitions for trattoria that I've seen before include "Place to eat" , "Italian restaurant" , "where Italians eat" , "Italian eating establishment" .)