Hot pudding served up without last of Victoria sponge (6)
I believe the answer is:
loofah
'sponge' is the definition.
(loofah is a type of sponge)
'hot pudding served up without last of victoria' is the wordplay.
'hot' becomes 'h' (abbreviation, eg on taps).
'pudding' becomes 'fool' (type of dessert).
'served up' shows that the letters should be reversed in order (in a down clue, going upwards).
'without' is an insertion indicator ('without' can be similar in meaning to 'outside').
'last of victoria' becomes 'a' (I can't justify this - if you can you should believe this answer much more).
'h'+'fool'='hfool'
'hfool' back-to-front is 'loofh'.
'loofh' placed around 'a' is 'LOOFAH'.
Can you help me to learn more?
(Other definitions for loofah that I've seen before include "Dishcloth gourd" , "Fibre used as a bath-scrub" , "Halo of the washing sponge?" , "Bathtime accessory" , "Kind of bathroom sponge for rubbing back" .)