Pressure is about English tarts (4)
I believe the answer is:
pies
'tarts' is the definition.
(I've seen this in another clue)
'pressure is about english' is the wordplay.
'pressure' becomes 'p' (abbreviation).
'about' is an insertion indicator.
'english' becomes 'e' (abbreviation).
'is' enclosing 'e' is 'ies'.
'p'+'ies'='PIES'
(Other definitions for pies that I've seen before include "Pastry crusts with fillings" , "Pastry snacks" , "food" , "Dishes baked in pastry-lining" , "Pastries" .)