Cake falls onto ice cream (4,5)
I believe the answer is:
drop scone
'cake' is the definition.
(I've seen this before)
'falls onto ice cream' is the wordplay.
'falls' becomes 'drops' (dropping is a kind of falling).
'onto' is a charade indicator (letters next to each other).
'ice cream' becomes 'cone' (cone can refer to an ice cream cone).
'drops'+'cone'='DROP-SCONE'
(Other definitions for drop scone that I've seen before include "cake" , "Scotch pancake" , "Girdlecake" , "Eating" , "Small and thick pancake" .)