Grandfather finished battered roll? Come and pay a visit! (7)
I believe the answer is:
popover
'battered roll? come and pay a visit' is the definition.
I can't judge whether this defines the answer.
'grandfather finished' is the wordplay.
'grandfather' becomes 'pop' (I am not sure about this - if you are sure you should believe this answer much more).
'finished' becomes 'over' (over can mean finished or ended).
'pop'+'over'='POPOVER'
Can you help me to learn more?
(Other definitions for popover that I've seen before include "Yorkshire pudding for one" , "batter pudding" , "individual portion of pudding" .)