Preheat oven to 425 degrees F. On a large sheet pan combine the chopped peppers, tomatoes, carrots, onion, and garlic. Coat with olive oil, salt, and pepper. Toss to combine and roast for 25-30 minutes until tender.
Heat a large stockpot or Dutch oven over medium-high heat. Add in the roasted vegetables, vegetable broth, and tomato sauce. Stir to combine, simmer for 5-6 minutes.
Using an immersion blender, carefully blend the mixture in the pot until smooth. Alternatively, you can use a blender, and carefully blend the mixture in batches and return back to the pot.
Once blended, stir in cream, dried basil, onion powder, garlic powder, and red pepper flakes. Serve garnished with a drizzle of olive oil and fresh basil.