Preheat the oven to 400 degrees. Line a large baking sheet with foil and set aside. Quarter the tomatoes and place on the pan. Add fresh basil on top of tomatoes then drizzle the olive oil across the top. Sprinkle salt and pepper on top. Cut the top of the garlic off and then wrap in foil. Place on the pan. Roast the tomatoes for 45 minutes, or until the skins start to shrivel. Allow to cool slightly, and then pour the tomatoes and basil into a blender. Remove the foil from the garlic and squeeze the cloves into the blender. Pulse until you reach your desired consistency. Add more basil, salt and pepper to taste. Warm if needed, before serving. Serve over cooked pasta.