Bread from birdhouse Mark's brought into lounge (7,4)
I believe the answer is:
cottage loaf
'bread' is the definition.
(I've seen this before)
'birdhouse mark's brought into lounge' is the wordplay.
'birdhouse' becomes 'cote' (I've seen this in another clue).
'mark' becomes 'tag' (tag is a kind of mark).
'brought into' means one lot of letters goes inside another.
'lounge' becomes 'loaf' (synonyms).
'cote' placed around 'tag' is 'cottage'.
'cottage'+'loaf'='COTTAGE LOAF'
'from' acts as a link.
(Another definition for cottage loaf that I've seen is " Style of bread".)