Charm of extremely bizarre sorceress (7)
I believe the answer is:
bewitch
'charm' is the definition.
('bewitch' can be a synonym of 'charm')
'extremely bizarre sorceress' is the wordplay.
'extremely' says to hollow out the word (remove centre letters).
'sorceress' becomes 'witch' (I've seen this before).
'bizarre' with its middle removed is 'be'.
'be'+'witch'='BEWITCH'
'of' is the link.
(Other definitions for bewitch that I've seen before include "Enchant - or curse" , "Put under a magic spell, or charm" , "Captivate" , "Fascinate - charm" , "Get intoxicated" .)