Most of porcelain pots including hot toast (4-4)
I believe the answer is:
chin-chin
'toast' is the definition.
(I've seen this before)
'most of porcelain pots including hot' is the wordplay.
'most of porcelain' becomes 'chin' (I can't justify this - if you can you should believe this answer much more).
'pots' means one lot of letters goes inside another (pot can mean to contain).
'including' becomes 'inc'.
'hot' becomes 'h' (abbreviation eg on taps).
'inc'+'h'='inch'
'chin' enclosing 'inch' is 'CHIN-CHIN'.
Can you help me to learn more?
(Other definitions for chin-chin that I've seen before include "Down the hatch!" , "good health ..." , "Cheers, bottoms up" .)