Stupid person presenting pudding to the Queen (6)
I believe the answer is:
duffer
'stupid person' is the definition.
The answer and definition can be both people as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
'pudding to the queen' is the wordplay.
'pudding' becomes 'duff' (duff is a kind of pudding).
'to the queen' becomes 'er' (Elizabeth Regina).
'duff'+'er'='DUFFER'
'presenting' acts as a link.
Can you help me to learn more?
(Other definitions for duffer that I've seen before include "Informally an inefficient person" , "Fogey" , "Incompetent person" , "Fed fur to informally think person" , "Fed fur to foolish person" .)