Just holding empty plate for all to see (6)
I believe the answer is:
openly
'for all to see' is the definition.
(out in the open)
'just holding empty plate' is the wordplay.
'just' becomes 'only' (synonyms).
'holding' indicates putting letters inside.
'empty' means to remove the middle letters.
'plate' with its centre removed is 'pe'.
'only' enclosing 'pe' is 'OPENLY'.
(Other definitions for openly that I've seen before include "In frank and candid manner" , "In public" , "Above board" , "Frankly, honestly" , "Candidly, without concealment." .)