Crossword Genius

Mashed potato father had right away (2,3,4,2,1,3)

Ross

I believe the answer is:

at the drop of a hat

'right away' is the definition.
(I've seen this in another clue)

'mashed potato father had' is the wordplay.
'mashed' is an anagram indicator.
'potato'+'father'+'had'='potatofatherhad'
'potatofatherhad' with letters rearranged gives 'AT THE DROP OF A HAT'.

(Other definitions for at the drop of a hat that I've seen before include "instantly" , "When pork pie downed" , "in no time at all" , "without delay" , "When a tile descends" .)

I've seen this clue in The Independent.
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