Improve dessert with directions (7)

I believe the answer is:
sweeten
'improve' is the definition.
The answer and definition can be both related to change as well as being verbs in their base form.
Maybe you can see an association between them that I can't see?
'dessert with directions' is the wordplay.
'dessert' becomes 'sweet' (synonyms).
'with' says to put letters next to each other.
'directions' becomes 'en' (east and north).
'sweet'+'en'='SWEETEN'
Can you help me to learn more?
(Other definitions for sweeten that I've seen before include "Seen wet (anag.)" , "put in sugar" , "placate" , "We teens! (anag)" , "Add sugar or honey" .)
