Paddy’s cereal (4)
I believe the answer is:
rice
This clue is a double definition.
'paddy's' is the first definition.
(thesaurus)
'cereal' is the second definition.
(rice is a kind of cereal)
(Other definitions for rice that I've seen before include "Asian staple food" , "Cereal plant" , "Lyricist Tim - dramatist Elmer" , "Cereal food" , "Cereal grain" .)