Preheat your oven to 200°C (400°F) and line a baking sheet with parchment paper.
Peel the sweet potatoes and carrots, then cut them into uniform chunks for even roasting.
Toss the chopped vegetables with 1 tablespoon of olive oil, salt, and pepper, making sure they’re well coated.
Spread the vegetables evenly on the prepared baking sheet and roast for 25 to 30 minutes, until they are golden and tender with a sweet, smoky aroma filling your kitchen.
While the vegetables roast, heat a large pot over medium heat and add 1 tablespoon of olive oil.
Add the chopped onion to the pot and cook, stirring occasionally, until it becomes translucent and fragrant, about 5 minutes.
Stir in the minced garlic and grated ginger, cooking for another minute until the mixture smells spicy and fresh.
Once the roasted vegetables are ready, add them to the pot with the sautéed aromatics.
Pour in the vegetable stock, bringing the mixture to a gentle simmer, and let it cook for about 10 minutes to meld the flavors.
Use an immersion blender directly in the pot, or transfer the soup in batches to a blender, blending until smooth and velvety. Be careful with hot liquids; vent the lid slightly when blending.
Taste the soup and add salt, pepper, and a squeeze of lemon juice if desired, to brighten the flavors.
Serve the soup hot, garnished with fresh herbs or a swirl of cream if you like, and enjoy its comforting, vibrant warmth.