Platter presented to soothe monarch (6)
I believe the answer is:
salver
'platter' is the definition.
(thesaurus)
'to soothe monarch' is the wordplay.
'to soothe' becomes 'salve' (I've seen this before).
'monarch' becomes 'R' (abbreviation for regina, e.g. in ER ).
'salve'+'r'='SALVER'
'presented' acts as a link.
(Other definitions for salver that I've seen before include "plate" , "Tray, sometimes silver" , "Serving tray" , "that is comforting" , "A heavy silver tray" .)