Preheat your oven to 425°F (220°C). Spread the cubed butternut squash and sliced carrots evenly on a baking sheet, then drizzle them with olive oil. Toss gently to coat each piece thoroughly.
Place the baking sheet in the oven and roast for about 35-40 minutes, until the vegetables are deeply golden and have a slight char on the edges. The aroma will be nutty and sweet as they caramelize.
Remove the roasted vegetables from the oven and let them cool for a few minutes until they are safe to handle. Transfer them to a blender or immersion blender.
Add the minced garlic and about half of the vegetable broth to the blender. Blend until smooth and creamy, stopping to scrape down the sides if necessary. You can adjust the liquid for your preferred consistency.
Pour the blended mixture into a pot and heat over medium-low. Gradually stir in the remaining vegetable broth, bringing the soup to a gentle simmer. Taste and season with salt and pepper as needed.
Cook the soup for about 10 minutes, allowing the flavors to meld and the texture to thicken slightly. Stir occasionally to prevent sticking.
Once the soup reaches a velvety texture and is heated through, taste again and adjust seasoning if necessary. Serve hot, garnished with a drizzle of olive oil or fresh herbs if desired.
