Cook offering horse? Not English, bad! (9)
I believe the answer is:
chargrill
'cook' is the definition.
(chargrilling is a type of cooking)
'horse? not english bad' is the wordplay.
I cannot quite understand how this works, but
'horse?' could be 'h' (synonyms) and 'h' is located in the answer.
'bad' could be 'ill' (associated in meaning) and 'ill' is found in the answer.
This explanation may well be incorrect...
'offering' acts as a link.
(Other definitions for chargrill that I've seen before include "put on barbecue" , "Cook quickly at a very high heat" , "Cook with bare flames" .)