Cold Shanghai smoked fish features crispy, sweet-savory marinated fish slices. A high protein, fresh appetizer perfect for family gatherings and celebrations.
Pat fish fillets dry, then cut into thick slices; set aside on paper towels to remove extra moisture.
In a bowl, whisk egg, then add cornstarch and flour to form a coating batter; toss the fish gently to coat each slice evenly.
Heat vegetable oil in a large skillet or wok over medium-high heat until shimmering (350°F); fry fish slices in small batches for 2–3 minutes per side until golden-brown and crispy. Drain well on rack.
In a saucepan, combine soy sauce, Shaoxing wine, sugar, dark soy, vinegar, five spice, sliced ginger, and salt; bring to a gentle simmer for 2 minutes to dissolve sugar and blend flavors. Add scallions and simmer another minute, then remove from heat.
Layer fish slices in a shallow dish and pour the warm marinade evenly over; let cool to room temperature, then refrigerate at least 1 hour before serving so flavors penetrate and texture firms up.