In tearoom, I served penny-pincher (5)
I believe the answer is:
miser
'penny-pincher' is the definition.
(I've seen this before)
'in tearoom i served' is the wordplay.
'in' says the answer is hidden in the clue.
'MISER' can be found hidden inside 'tearoom i served'.
(Other definitions for miser that I've seen before include "Hoarder of money and possessions" , "Niggard" , "One sparing with money" , "Person who hoards money" , "Someone close" .)