Prepared lunch for Arabians - it's what one did as the sun shone (4,3)
I believe the answer is:
made hay
'arabians it's what one did as the sun shone' is the definition.
I don't know anything about this answer so I can't judge whether this works.
'prepared lunch' is the wordplay.
'prepared' becomes 'made' ('make' can be a synonym of 'prepare').
'lunch' becomes 'hay' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'made'+'hay'='MADE HAY'
'for' acts as a link.
Can you help me to learn more?
(Another definition for made hay that I've seen is " Seized an opportunity".)