Happy to eat soft chocolate bar (6)
I believe the answer is:
galaxy
'chocolate bar' is the definition.
'Galaxy' can be an answer for 'bar' (chocolate bar). I am not certain of the 'chocolate' bit.
'happy to eat soft' is the wordplay.
'happy' becomes 'gay' (similar in meaning).
'to eat' is an insertion indicator.
'soft' becomes 'lax' (synonyms).
'gay' enclosing 'lax' is 'GALAXY'.
Can you help me to learn more?
(Other definitions for galaxy that I've seen before include "Assemblage of stars" , "System of stars - assembly of talent" , "A lot of stars" , "Spiral, elliptical, group of stars" , "Large star system" .)