Boy turned up with hot food (4)
I believe the answer is:
nosh
'food' is the definition.
(nosh is a kind of food)
'boy turned up with hot' is the wordplay.
'boy' becomes 'son' (male child).
'turned up' is a reversal indicator.
'with' means one lot of letters go next to another.
'hot' becomes 'h' (abbreviation eg on taps).
'son' reversed gives 'nos'.
'nos'+'h'='NOSH'
(Other definitions for nosh that I've seen before include "'Food, grub (4)'" , "Eat (sl.)" , "Fare" , "Food - eat greedily" , "(Eat) a snack" .)