1. Combine vinegar, salt, sugar, lavender and lemon with 3 cups water in a pot and bring to a boil. Cook for 1 minute, then cool down. Once cooled, place into a large container with the fish. Let brine for 12 minutes, then remove and pat dry.
2. While fish is brining, place a large pan on high heat. Add olive oil and tomatoes to pan. Cook for 10 minutes while stirring constantly to break tomatoes down. Add garlic and cook for 2 minutes. Toss in the basil and tomato sauce. Bring to a boil, then reduce to a simmer.
3. Season fish with salt and pepper, chives and parsley. Heat a large pan with a drizzle of olive oil and lay in to sear. Sear on each side for 1-2 minutes.
4. Once seared, transfer fish to tomato sauce and simmer. Cook fish for another 5 minutes on low heat with a lid on the pan.