Of food, a pile left out? (3)
I believe the answer is:
pie
'of food' is the definition.
'pie' can be an answer for 'food' (pie is a kind of food). I am not certain of the 'of' bit.
'a pile left out?' is the wordplay.
'left' becomes 'l' (common abbreviation).
'out?' suggests deleting specific letters.
'pile' with 'l' taken away is 'PIE'.
Can you help me to learn more?
(Other definitions for pie that I've seen before include "Cooked food" , "In the sky, it's an unrealistic prospect" , "Slapstick missile" , "Bird - dish - mixed type" , "Confused, mixed type" .)