01 - Preheat oven to 400°F. Line a baking sheet with parchment paper.
02 - Arrange halved tomatoes, onion, garlic, and carrot on the baking sheet. Drizzle with olive oil and sprinkle with 1/2 tsp salt and black pepper.
03 - Roast vegetables for 25–30 minutes until tomatoes are soft and edges are caramelized.
04 - In a large pot, melt butter over medium heat. Add roasted vegetables, dried basil, thyme, and red pepper flakes. Stir for 2 minutes.
05 - Pour in vegetable broth. Bring to a boil, reduce heat, and simmer for 10 minutes.
06 - Using an immersion blender or carefully transfer to a blender in batches, puree the soup until smooth.
07 - Stir in heavy cream, taste, and adjust seasoning as needed.
08 - Serve hot, garnished with fresh basil and a swirl of cream if desired.