Callas recollected a famous opera venue (2,5)
I believe the answer is:
la scala
'opera venue' is the definition.
(Milanese opera house)
'callas recollected a' is the wordplay.
'recollected' is an anagram indicator (letters recollected and rearranged).
'callas' anagrammed gives 'lascal'.
'lascal'+'a'='LA SCALA'
'famous' acts as a link.
I am not very happy about this link. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for la scala that I've seen before include "Milanese opera house" , "Italian opera house" , "A Callas may find way to Milan's famous opera house" , "music centre" , "where Toscanini was musical director" .)