Hole in a cooking appliance (3)
I believe the answer is:
gap
'hole' is the definition.
(thesaurus)
'in a cooking appliance' is the wordplay.
'in' says the answer is hidden in the clue.
'GAP' can be found hidden inside 'cooking appliance'.
(Other definitions for gap that I've seen before include "Break in continuity" , "A breach or pass" , "Small opening" , "A break in something continuous, like a hedge" , "Breach or lacuna" .)