Preheat the oven to 400 degrees. Rinse the prawns in cold water and drain. Peel the prawns, leaving the head and tail intact, discarding the shells. Season with salt and pepper. Place the prawns in a large oven-proof baking dish. In a large saute pan, heat the olive oil. Add the onions. Season with salt and pepper. Saute for 3 to 4 minutes, or until translucent. Add the tomatoes, garlic, and herbs. Saute for 1 minute. Add the wine and bring the liquid to a boil. Reduce to a simmer and cook for 2 minutes. Pour the mixture over the prawns. Sprinkle the top with the cheese. Place in the oven and roast for 8 minutes. Remove from the oven and garnish with parsley.