Port covering very dry dish (7)
I believe the answer is:
risotto
'dish' is the definition.
(risotto is a kind of dish)
'port covering very dry' is the wordplay.
'port' becomes 'rio' (Rio de Janeiro is a port).
'covering' means one lot of letters goes inside another.
'very' becomes 'so' (both can mean 'extremely').
'dry' becomes 'tt' (abbreviation for teetotal).
'so'+'tt'='sott'
'rio' placed around 'sott' is 'RISOTTO'.
(Other definitions for risotto that I've seen before include "Italian course" , "F" , "Rice/stock dish" , "Main course" , "dishy thing!" .)