Green sauce in pot, dish stirred around beginning to thicken (15)
I believe the answer is:
Here is my best explanation:
'green' is the definition.
'sauce in pot dish stirred around beginning to thicken' is the subsidiary indication.
'stirred' indicates anagramming the letters.
'around' indicates putting letters inside.
'beginning to' indicates taking the first letters.
The first letter of 'thicken' is 't'.
'sauceinpotdish' with letters rearranged gives 'unsophisicated'.
'unsophisicated' placed around 't' is 'unsophisticated'.
(Other definitions for unsophisticated that I've seen before include "straightforward", "Simple", "crude", "Lacking experience", "green" and "Green".)