Preheat your oven to 400”F.
Meanwhile slice the tomatoes and onion into wedges, and the peppers into rounds or thin strips.
Add the tomatoes, peppers, onions and bay leaf to a large roasting dish. Drizzle over the top with the olive oil and season with the sea salt. Give it a gentle toss to coat.
Roast in the preheated oven for 1 hour, stirring gently half way.
Adjust seasonings to your taste with more sea salt. Discard bay leaves and serve hot over polenta, finished with a nice drizzle of olive oil, a squeeze of lemon and garnished with the basil leaves.