A rising desire to entertain brothers providing heavenly food (8)
I believe the answer is:
ambrosia
'heavenly food' is the definition.
(ambrosia is the food of the greek gods)
'a rising desire to entertain brothers' is the wordplay.
'rising' is a reversal indicator (going up in a down clue).
'desire' becomes 'aim' (I've seen this in another clue).
'to entertain' is an insertion indicator.
'brothers' becomes 'bros'.
'aim' reversed gives 'mia'.
'mia' enclosing 'bros' is 'mbrosia'.
'a'+'mbrosia'='AMBROSIA'
'providing' is the link.
(Other definitions for ambrosia that I've seen before include "Gods' dinner?" , "Wonderful food" , "fine fuel" , "I'm so Arab (anagram)" , "luxury food" .)