Cosy up with chocolate provider (6)
I believe the answer is:
nestle
I believe this clue is a double definition.
'cosy up' is the first definition.
(to nestle against something is get cosy next to it)
'chocolate provider' is the second definition.
(chocolate manufacturer)
'with' is the link.
(Other definitions for nestle that I've seen before include "Cuddle closely" , "Cuddle or snuggle up" , "Srttle comfortably" , "Swiss-based multinational food company, founded 1905" , "Lie safely" .)