Talk of memories I'm sincere about (9)
I believe the answer is:
reminisce
'talk of memories' is the definition.
Although both the answer and definition are verbs in their base form, I can't understand how one could define the other.
'i'm sincere about' is the wordplay.
'about' indicates an anagram.
'im'+'sincere'='imsincere'
'imsincere' anagrammed gives 'REMINISCE'.
Can you help me to learn more?
(Other definitions for reminisce that I've seen before include "Have fond recollections" , "Talk of past events" , "Look back at events" , "Remember past" , "Recount memories" .)