Preheat oven to 400°F. In a foil lined baking dish combine tomatoes and garlic. Coat tomatoes with olive oil and season with salt and pepper to taste. Bake tomatoes for 20-25 minutes or until the tomatoes begin to look wrinkled and release juice.
In a medium size baking dish, stir together roasted tomatoes, shrimp, oregano, and red pepper flakes.
Place baking dish into the oven and bake for 10-15 minutes or until the shrimp turn pink and reach an internal temperature of 165°F. Remove dish from the oven and sprinkle over Parmesan cheese in piles so some of the shrimp and tomatoes peek through. Finish cooking the shrimp under the broiler until cheese is melted and bubbly. Remove from the broiler, sprinkle with fresh basil and serve with slices of toasted sourdough bread.