Hummus's key ingredient, according to Spooner, is fruit of mallow (4-6)

'hummus's key ingredient according to spooner is fruit' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'mallow' is the wordplay.
I cannot really understand how this works, but
'mallow' could be 'cheese' (cheese is a kind of mallow) and 'cheese' is found in the answer.
The remaining letters 'pick' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).

'of' is the link.

Can you help me to learn more?