Artist dunking pencil into beer (9)
I believe the answer is:
portrayer
'artist' is the definition.
(I know that portrayer is a type of painter)
'pencil into beer' is the wordplay.
'pencil' becomes 'ray' (I have seen 'Pencil of light ' mean 'ray' so perhaps 'pencil' could also mean 'ray').
'into' means one lot of letters goes inside another.
'beer' becomes 'porter' (type of beer).
'ray' inserted into 'porter' is 'PORTRAYER'.
'dunking' acts as a link.
I am not very happy about this link. It may belong to another bit of the clue.
(Another definition for portrayer that I've seen is " Artist".)