Meals regularly served with hot potatoes (4)
I believe the answer is:
mash
'potatoes' is the definition.
(mashed potato)
'meals regularly served with hot' is the wordplay.
'regularly served' indicates alternate letters.
'with' is a charade indicator (letters next to each other).
'hot' becomes 'h' (abbreviation, eg on taps).
The alternating letters of 'meals' are 'mas'.
'mas'+'h'='MASH'
(Other definitions for mash that I've seen before include "Crush into a soft, pulpy state" , "Accompaniment of bangers" , "Black comedy film set in Korean War" , "It goes well with sausages" , "Pulped potatoes" .)