Preheat the oven to 200°C (400°F) and line a large baking sheet or casserole dish with parchment paper (paper is optional but prevents sticking).
Roughly chop the sweet potato, peppers, and onion. Add to the baking sheet with the olive oil, salt, pepper, hot pepper, cumin, and paprika. Use your hands to mix until the vegetables are evenly coated.
1 medium sweet potato, 2 large red peppers, 1 medium onion, 1 tablespoon olive oil, 1 teaspoon sea salt, ½ teaspoon black pepper, ½ teaspoon hot pepper flakes, ¼ teaspoon cumin seeds, ¼ teaspoon smoked paprika
Roast for 30-40 minutes, until the vegetables are cooked through and the edges start to darken. The time needed will depend on how crowded the baking sheet is.
Once the vegetables are done, place in a pot (if using an immersion blender) or heat-safe* blender. Add the vegetable broth and blend until very smooth, a couple of minutes.
400-500 ml (1 ⅔ - 2 cups) vegetable broth
Serve hot, topped with optional cream or yogurt and fresh herbs. This can be stored in the refrigerator for up to three days and freezes well.
Notes
* If you don't have a heat-safe blender or immersion blender, you'll have to let the roasted vegetables cool before blending with the broth. Reheat slowly in a pot on the stove top after blending and serve hot.