Newly sealed variety of cheese (11)
I believe the answer is:
wensleydale
'cheese' is the definition.
(thesaurus)
'newly sealed variety' is the wordplay.
'variety' indicates anagramming the letters.
'newly'+'sealed'='newlysealed'
'newlysealed' is an anagram of 'WENSLEYDALE'.
'of' is the link.
(Other definitions for wensleydale that I've seen before include "Wallace's favourite cheese" , "Say, we'll need (anag); a cheese" , "Yorkshire cheese" , "4 across" , "White crumbly variety of cheese" .)