Cleaning my bananas in a threatening way (10)

I believe the answer is:

menacingly

'in a threatening way' is the definition.
(I know this)

'cleaning my bananas' is the wordplay.
'bananas' indicates anagramming the letters (informal term for mad).
'cleaning'+'my'='cleaningmy'
'cleaningmy' is an anagram of 'MENACINGLY'.

(Another definition for menacingly that I've seen is " In threatening manner".)

I've seen this clue in The Daily Express.

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