01 - Set oven temperature to 425°F.
02 - Cut red bell peppers in half, remove seeds and stems; halve tomatoes.
03 - Place peppers cut side down, tomatoes cut side up, onion, and garlic on a baking sheet. Drizzle with 1 tablespoon olive oil; season with salt and pepper.
04 - Roast for 25 to 30 minutes until peppers are charred and vegetables are tender.
05 - Allow peppers to cool slightly, then remove and discard skins.
06 - Heat remaining 1 tablespoon olive oil in a large pot over medium heat. Add roasted vegetables, basil, thyme, and red pepper flakes; cook while stirring for 2 minutes.
07 - Pour in vegetable broth, bring to a simmer, and cook for 10 minutes.
08 - Blend soup using an immersion blender or in batches with a countertop blender until smooth.
09 - Stir in heavy cream, taste, and adjust salt and pepper as necessary.
10 - Warm gently for 2 minutes, then serve hot.