A fight in Howth beside empty allotment - wow! (3,5,4)

I believe the answer is:

how about that

I'm a little stuck... Click here to teach me more about this clue!

'empty allotment wow' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'a fight in howth beside' is the wordplay.
'a fight' becomes 'about' (I can't explain this - if you can you should believe this answer much more).
'in' means one lot of letters goes inside another.
'beside' becomes 'at'.
'about' put within 'howth' is 'howaboutth'.
'howaboutth'+'at'='HOW ABOUT THAT'

Can you help me to learn more?

I've seen this clue in The Irish Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.