In a bowl, combine the cherry tomatoes, olives, red onion, and garlic. Season with Tuscan Herb seasoning, oregano, salt, pepper, olive oil, and red wine vinegar. Toss well and let marinate while preparing the fish.
Lightly season the cod with salt, pepper, and a sprinkle of Tuscan Herb seasoning. Dredge each fillet lightly in flour, shaking off any excess.
Add olive oil and butter to the griddle. Once the butter is melted and bubbling, place the cod on the griddle and cook for 3–4 minutes per side, until golden and cooked through. Remove and set aside.
Add the marinated vegetable mixture to the griddle and spread into an even layer. Cook for 3–4 minutes until the tomatoes begin to blister and the onions soften.
Return the cod to the griddle, nestling it into the vegetables. Spoon some of the juices over the fish and cook together for 1–2 minutes to warm through.
Finish with fresh parsley and a light drizzle of olive oil.
Serve immediately with crusty Italian bread for soaking up the sauce.