Step 1

Cut 2 medium scallions crosswise into 2-inch pieces. Halve or quarter the pieces lengthwise into thin strips.

Step 2

Pat 4 red snapper fillets dry with paper towels. Season all over with 1 teaspoon garlic powder, 1 teaspoon black pepper, and 1/2 teaspoon kosher salt.

Step 3

Heat 1/2 cup vegetable oil in a large nonstick frying pan over medium-high heat until shimmering. Working in batches if needed, add the fish skin-side down in a single layer. Fry, gently pressing down on the fish with a flat spatula occasionally so that it stays flattened, until cooked through and the skin is crisp, 4 to 5 minutes per side. Transfer the fish to a wire rack.

Step 4

Turn off the heat. Pour the oil into a heatproof bowl. Wipe out the pan with a paper towel. Return 2 tablespoons of the oil to the pan.

Step 5

Add the scallions, 1 thinly sliced medium yellow onion, 1 matchstick-cut medium carrot, 1/2 thinly sliced medium red bell pepper, 1 tablespoon matchstick-cut ginger, 3 fresh thyme sprigs, 1 pierced Scotch bonnet pepper, 3 whole allspice berries, and 2 dried bay leaves to the pan. Cook over medium heat until the onions and carrots are crisp-tender, about 5 minutes.

Step 6

Stir in 1/3 cup distilled white vinegar, 2 tablespoons water, 1 tablespoon plus 1 teaspoon granulated sugar, and 1 1/2 teaspoons kosher salt. Simmer until the sugar and salt dissolve and the liquid reduces slightly, 2 to 3 minutes.

Step 7

Turn off the heat. Remove and discard the Scotch bonnet, allspice, bay leaves, and thyme stems. Serve the vegetables and sauce over the fish.