Plate lifted off one's trolley, US cookies (6,8)
I believe the answer is:
animal crackers
'us cookies' is the definition.
I don't know anything about this answer so I cannot judge whether this works.
'plate lifted off one's trolley' is the wordplay.
'plate' becomes 'lamina' (anatomical term for a plate or layer).
'lifted' says the letters should be written backwards (going up in down clue).
'off one's trolley' becomes 'crackers' (both can mean mad).
'lamina' in reverse letter order is 'animal'.
'animal'+'crackers'='ANIMAL CRACKERS'
Can you help me to learn more?
(Other definitions for animal crackers that I've seen before include "Picture" , "film" .)