Policemen stand around consuming a mince dish (4,4)
I believe the answer is:
meat loaf
'mince dish' is the definition.
'meat loaf' can be an answer for 'dish' (meat loaf is a kind of dish). I'm not sure about the 'mince' bit.
'policemen stand around consuming a' is the wordplay.
'policemen' becomes 'Met' (Metropolitan Police).
'stand around' becomes 'loaf' (I can't justify this - if you can you should give a lot more credence to this answer).
'consuming' is an insertion indicator.
'met'+'loaf'='metloaf'
'metloaf' enclosing 'a' is 'MEAT-LOAF'.
Can you help me to learn more?
(Other definitions for meat loaf that I've seen before include "main course" , "Bully-beef etc" , "Mince dish and pop singer" , "food" , "Baked savoury dish" .)