Preheat your oven to 200°C (390°F). Peel the carrots and ginger, then cut the carrots into 2-inch chunks and thinly slice the ginger.
Spread the carrots and ginger evenly on a baking sheet. Drizzle with olive oil and toss gently to coat all pieces thoroughly.
Roast the vegetables in the oven for about 25-30 minutes, until the carrots are deeply caramelized and slightly charred at the edges, filling your kitchen with a smoky, sweet aroma.
Meanwhile, pour the vegetable broth into a large pot and bring it to a gentle simmer over medium heat.
Once the roasted vegetables are ready, transfer them to the simmering broth. Let everything cook together for about 10 minutes to meld the flavors.
Use an immersion blender directly in the pot to blend the soup until smooth and velvety, or carefully transfer in batches to a blender and puree until silky.
Squeeze fresh lemon juice into the soup, then season with salt and pepper to taste. Blend briefly again to incorporate the flavors evenly.
Serve the soup hot, garnished with a drizzle of cream, chopped herbs, or a sprinkle of toasted seeds if desired. Enjoy the vibrant color and rich, layered flavors with each spoonful.