Bizarre mania for stuffing cheese in slow cooker (4-5)
I believe the answer is:
bain-marie
'slow cooker' is the definition.
'bizarre mania for stuffing cheese' is the wordplay.
'bizarre' indicates an anagram.
'for stuffing' indicates putting letters inside.
'cheese' becomes 'brie' (Brie is an example).
'mania' anagrammed gives 'ainma'.
'ainma' going into 'brie' is 'BAIN-MARIE'.
'in' acts as a link.
(Other definitions for bain-marie that I've seen before include "Cooking pan with water" , "Water-filled slow cooker" .)