Preheat your oven to 400°F (200°C) and spread the butternut squash chunks and sliced carrots on a baking sheet. Drizzle with olive oil, sprinkle with salt and pepper, and toss to coat evenly.
Roast the vegetables in the oven for about 25-30 minutes, until they are tender and caramelized around the edges with a sweet aroma filling the kitchen.
Meanwhile, in a large pot, sauté the diced onion and minced garlic in a tablespoon of olive oil over medium heat until the onion becomes translucent and fragrant—about 5 minutes.
Add the roasted vegetables to the pot with the sautéed aromatics, then pour in the vegetable broth and stir in ground cumin. Bring the mixture to a gentle simmer.
Using an immersion blender or a regular blender, blend the soup until completely smooth and creamy—be cautious blending hot liquids, and do so in batches if necessary.
Return the pureed soup to the heat and taste for seasoning, adjusting with salt and pepper as needed. Once heated through, ladle into bowls.
Serve the soup hot, garnished with a drizzle of olive oil or fresh herbs if desired, and enjoy its rich, velvety texture and sweet roasted flavor.
