Sample portion of pasta's terrible (6)
I believe the answer is:
taster
'sample' is the definition.
(thesaurus)
'portion of pasta's terrible' is the wordplay.
'portion of' says the answer is hidden in the clue.
'TASTER' is hidden in the letters of 'pastas terrible'.
(Other definitions for taster that I've seen before include "One trying" , "Art set (anag.)" , "Brief sample" , "Quality assurance worker" , "A sample to try" .)