Very little can be sent out, sugar (7)
I believe the answer is:
sweeten
'sugar' is the definition.
(I've seen this before)
'very little can be sent out' is the wordplay.
'very little' becomes 'wee' (I've seen this in another clue).
'can be' indicates anagramming the letters.
'out' is an insertion indicator.
'sent' anagrammed gives 'sten'.
'wee' placed into 'sten' is 'SWEETEN'.
(Other definitions for sweeten that I've seen before include "temper" , "Appease" , "We teens! (anag)" , "Make less bitter" , "Make sugary or saccharine" .)