Picture board on gold (7)
I believe the answer is:
tableau
'picture' is the definition.
(a tableau is a picture or display)
'board on gold' is the wordplay.
'board' becomes 'table' (both can mean food).
'on' says to put letters next to each other.
'gold' becomes 'Au' (Au is the chemical symbol for gold).
'table'+'au'='TABLEAU'
(Other definitions for tableau that I've seen before include "Living picture" , "Frozen stage scene" , "Figures making a scene" , "Staged scene" , "pictorial presentation" .)