Man weary again cooking for a number at Christmas (4,2,1,6)
I believe the answer is:
away in a manger
'a number at christmas' is the definition.
I know nothing about this answer so I can't judge whether this works.
'man weary again cooking' is the wordplay.
'cooking' indicates an anagram (cook can mean to falsify or distort).
'man'+'weary'+'again'='manwearyagain'
'manwearyagain' anagrammed gives 'AWAY IN A MANGER'.
'for' is the link.
Can you help me to learn more?
(Other definitions for away in a manger that I've seen before include "Christmas carol" , "Familiar tune" , "song?" .)