Retired cleric eating energy food, such as cake (10)

'as cake' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'retired cleric eating energy food' is the wordplay.
'retired' is a reversal indicator.
'cleric' becomes 'Rev' (abbreviation for Reverend).
'eating' indicates putting letters inside.
'energy' becomes 'e' (physics symbol as in E=mcr).
'food' becomes 'grubeg' (I can't explain this - if you can you should give a lot more credence to this answer).
'e'+'grubeg'='egrubeg'
'rev' going around 'egrubeg' is 'regrubegev'.
'regrubegev' written backwards gives 'VEGEBURGER'.

'such' is the link.