Food supplier of three queens? (7)
I believe the answer is:
caterer
'food supplier' is the definition.
(I've seen this before)
'three queens?' is the wordplay.
'three queens?' means three replacements for 'queen'.
'queen' becomes 'cat' (a queen is a female cat).
'queen' becomes 'ER' (abbreviation for Elizabeth Regina).
'queen' becomes 'ER' (abbreviation for Elizabeth Regina).
'cat'+'er'+'er'='CATERER'
'of' acts as a link.
(Other definitions for caterer that I've seen before include "Someone providing food and service" , "One supplies" , "Terrace (anag.)" , "One supplying needs" , "One supplying cheer" .)