Advent roast in a church with fruit stuffing (10)
I believe the answer is:
appearance
'advent' is the definition.
(I've seen this before)
'roast in a church with fruit stuffing' is the wordplay.
'roast' becomes 'pan roast' (panning roast is a kind of roasting).
'in' means one lot of letters goes inside another.
'church' becomes 'CE' (abbreviation for Church of England).
'with' is an insertion indicator.
'fruit stuffing' becomes 'pear' (I can't explain this - if you can you should give a lot more credence to this answer).
'a'+'ce'='ace'
'pan' going within 'ace' is 'apance'.
'apance' going around 'pear' is 'APPEARANCE'.
Can you help me to learn more?
(Other definitions for appearance that I've seen before include "Advent" , "Act of being present - look" , "it seems" , "air" , "manifestation" .)