Preheat the Oven: Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper or foil for easy cleanup.Season the Fish: Descale, wash, and pat the branzino dry using clean paper towels — dry skin equals crisp skin. Make two slits on each side of the fish. Season the inside and outside with salt, pepper, and garlic powder. Then drizzle olive oil over the fish. Add Fresh Aromatics: Stuff the cavity with fresh dill, tomato pieces, and onion slices for flavor and moisture as it bakes.
Roast the Fish: Place the fish on the prepared baking sheet and drizzle with lemon juice. Roast for 20–25 minutes, or until the skin is golden and the flesh flakes easily with a fork.Make the Sauce: In a small saucepan, while the fish roasts, whisk together olive oil, white wine vinegar, water, lemon juice, red pepper flakes, salt, and pepper. Bring to a boil over medium-high heat.Serve: Drizzle the warm sauce over the roasted Branzino. Garnish with more fresh dill or lemon wedges if desired.
