An East Coast tradition (although typically made with salt cod), these fresh patties are a tasty addition to your weeknight supper repertoire. Serve with steamed mixed veggies or salad for a nutritious supper.
Stir 1/4 cup each of the breadcrumbs and egg together until combined; stir in the mustard powder, lemon zest, garlic, salt and pepper. Pulse the cod in the bowl of a food processor, fitted with a metal blade, until uniformly chopped. Add the cod, potatoes, green onions, celery and parsley to the egg mixture; mix gently until combined.
Divide the mixture into 6 equal portions and form into 3/4-inch (2 cm) thick patties. Place the remaining egg and breadcrumbs in separate shallow dishes; dip each patty in the egg and then coat in the breadcrumbs (discard any leftover egg and breadcrumbs).
Heat the oil in a large, non-stick skillet and set over MEDIUM-HIGH heat. Place the patties in the skillet and cook for 3 to 4 minutes per side or until golden and fish is cooked.