Preheat oven to 425°F (220°C).
Toss red peppers and cauliflower with 1 tbsp olive oil, salt, and pepper; roast 20–25 minutes.
Heat remaining olive oil in a large pot; sauté onion for 5 minutes until soft.
Add garlic and smoked paprika; cook 1–2 minutes until fragrant.
Transfer roasted vegetables to the pot; pour in vegetable broth.
Simmer for 10 minutes to meld flavors.
Blend soup until smooth using immersion blender or regular blender.
Stir in plant-based cream; adjust seasoning. Serve hot with optional garnish.