Pat the white fish fillets dry with paper towels. Preheat the oil in a deep skillet to about 350°F (175°C).

In a shallow dish, combine the all-purpose flour, salt, and black pepper. Dredge the fish fillets in the flour mixture.

Beat the eggs in a bowl. Dip each floured fish fillet into the egg wash, allowing excess to drip off.

Coat each egg-dipped fish fillet with panko breadcrumbs.

Fry the coated fish fillets in hot oil for about 3-4 minutes on each side until golden brown.

Transfer the fried fish fillets onto a plate lined with paper towels to drain excess oil.

Toast the sandwich buns cut-side down in a pan until warm and slightly crisp.

Spread your choice of sauce on both sides of the toasted buns. Layer with lettuce, tomato slices, and fried fish fillet.

Optionally, garnish with fresh herbs and serve with lemon wedges.