Pig's ear topping ex-PM's potato bites (4,6)
I believe the answer is:
Here is my best explanation:
'potato bites' is the definition.
'pig's ear topping ex-pm's' is the wordplay.
'pig's ear' becomes 'hash'.
'topping' says to put letters next to each other.
'ex-pm's' becomes 'browns' (Gordon Brown).
(Other definitions for hash browns that I've seen before include "breakfast? Part of it, perhaps" and "potato dish".)