Step 1

Preheat oven-safe serving platter in 250˚F oven.

Step 2

Set out one large, clean plate or platter and one medium plate. Pour panko breadcrumbs onto medium plate.

Step 3

Place cooked fish into a large bowl and flake into small pieces with a fork. Add sour cream, egg, celery, capers, green onion, salt, and pepper; stir to combine. Scoop out 1/8 of the mixture and use your hands to gently pack into a patty. Place on plate with panko crumbs and gently coat all sides with crumbs; transfer to platter. Repeat with remaining mixture.

Step 4

Heat 2 tablespoons oil in a large skillet over medium heat until hot. Place 4 fish cakes in skillet and cook until crumbs are crisp and golden brown, pressing down gently with spatula to compress; about 5 minutes per side (turn gently). Transfer cooked fish cakes to warm platter. Repeat process with remaining oil and fish cakes.

Step 5

Serve fish cakes hot with lemon wedges if desired.