King and Queen feast outside? (3)

I believe the answer is:

bbq

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'feast outside?' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'king and queen' is the wordplay.
'king' becomes 'bb' (I can't justify this - if you can you should believe this answer much more).
'and' says to put letters next to each other.
'queen' becomes 'Q' (chess abbreviation).
'bb'+'q'='BBQ'

Can you help me to learn more?

I've seen this clue in The Guardian.

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