01 -  Preheat oven to 400°F. Line a baking sheet with parchment paper. 
 02 -  Place halved tomatoes cut side up on the prepared baking sheet. Drizzle with 1 tablespoon olive oil and season with salt and black pepper. 
 03 -  Cut the top off the garlic head to expose the cloves. Drizzle with 1 tablespoon olive oil and wrap tightly in aluminum foil. Place garlic alongside tomatoes on the baking sheet. 
 04 -  Roast in oven for 30 to 35 minutes until tomatoes are caramelized and garlic cloves are soft. Remove from oven and let cool slightly. 
 05 -  In a large pot, heat 1 tablespoon olive oil over medium heat. Add chopped onion and sauté for 5 minutes until softened. 
 06 -  Squeeze roasted garlic cloves from skins into the pot. Add roasted tomatoes with juices, broth, basil leaves, and optional red pepper flakes. 
 07 -  Use an immersion blender to purée the mixture directly in the pot, or transfer to a stand blender in batches until velvety smooth. 
 08 -  Return blended soup to the pot if needed. Stir in heavy cream and simmer gently for 5 to 10 minutes to blend flavors. Adjust seasoning as necessary. 
 09 -  Ladle soup into bowls and garnish with fresh basil leaves, a swirl of cream, or crispy roasted tomato pieces as desired.