Green sauce in pot, dish stirred around beginning to thicken (15)
I believe the answer is:
unsophisticated
'green' is the definition.
(thesaurus)
'sauce in pot dish stirred around beginning to thicken' is the wordplay.
'stirred' indicates an anagram.
'around' is an insertion indicator.
'beginning to' indicates taking the first letters.
The first letter of 'thicken' is 't'.
'sauce'+'in'+'pot'+'dish'='sauceinpotdish'
'sauceinpotdish' is an anagram of 'unsophisticaed'.
'unsophisticaed' enclosing 't' is 'UNSOPHISTICATED'.
(Other definitions for unsophisticated that I've seen before include "Simple" , "crude" , "Lacking experience" , "green" , "straightforward" .)