List from the two of us, very informally (4)
I believe the answer is:
menu
'list' is the definition.
(menu is a kind of list)
'the two of us very informally' is the wordplay.
I cannot quite see how this works, but
'us' could be 'me' ('us' can mean 'mean' in some UK dialects) and 'me' is located in the answer.
The remaining letters 'nu' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
'from' is the link.
(Other definitions for menu that I've seen before include "Options available" , "Choice of dishes" , "List of options" , "Tariff" , "Bill of fare" .)