Perhaps mashed potatoes can be prepared in odd diets (6)
I believe the answer is:
dances
'perhaps mashed potatoes' is the definition.
(the mashed potato is a humorous dance move)
'can be prepared in odd diets' is the wordplay.
'be prepared' indicates an anagram.
'in' indicates putting letters inside.
'odd' indicates alternate letters.
The alternate letters of 'diets' are 'des'.
'can' anagrammed gives 'anc'.
'anc' inserted inside 'des' is 'DANCES'.
(Other definitions for dances that I've seen before include "Eg, tango and samba" , "Jigs" , "Balls" , "Moves to music" , "Trips the light fantastic" .)