Soak food before cooking (8)
I believe the answer is:
marinate
'soak food before cooking' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for marinate that I've seen before include "Pickle" , "Soak meat, fish etc" , "Soak in spiced liquid" , "Steep before cooking" , "Soak or steep meat or fish" .)