Slice the fish into 12 fingers, each about 3cm thick. 

Put the seasoned flour, egg and breadcrumbs into 3 separate shallow bowls. 

Dust the fish pieces first in the flour, then coat well in the egg, and cover completely in the breadcrumbs. 

Heat the oil in a large frying pan. 

Add the fish fingers and fry for 8 mins, turning occasionally, until golden and cooked through. 

Meanwhile, add the peas to a small pan of boiling water. 

Cook for 4 mins until really tender. 

Drain, tip into a bowl with the butter, zest and mint, and roughly mash with a potato masher. 

Serve and enjoy.