Fat queen in pantry (6)
I believe the answer is:
larder
'pantry' is the definition.
(synonyms)
'fat queen' is the wordplay.
'fat' becomes 'lard' (lard is a kind of fat).
'queen' becomes 'ER' (abbreviation for Elizabeth Regina).
'lard'+'er'='LARDER'
'in' is the link.
(Other definitions for larder that I've seen before include "Room or cupboard for storing food" , "Place where food is kept" , "Pantry" , "Buttery" , "Cool store" .)