His products could make you stout, and so could he! (6)
I believe the answer is:
brewer
'his products could make you stout and so could he' is the definition.
(cryptic definition: stout is a type of beer)
'he' is the wordplay.
I cannot really understand how this works, but
'he' could be 'brew' and 'brew' is found in the answer.
The remaining letters 'er' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for brewer that I've seen before include "who prepares the tea?" , "Maker of beer - "Phrase and Fable" dictionary editor" , "Maker of beer etc" , "I make tea" , "Tendency to seek perfection" .)