Very little money inspires Yankee oil producer (7)
I believe the answer is:
soybean
'oil producer' is the definition.
'very little money inspires yankee' is the wordplay.
'very' becomes 'so' (I've seen this in other clues).
'little money' becomes 'bean' (as in phrases like 'not a bean').
'inspires' means one lot of letters goes inside another (inspire means to breathe in).
'yankee' becomes 'y' (phonetic alphabet: alpha, bravo, charlie etc.).
'so'+'bean'='sobean'
'sobean' enclosing 'y' is 'SOYBEAN'.
(Other definitions for soybean that I've seen before include "Vegetable source of protein" , "American vegetable" .)