For a richer flavor, roast the butternut squash and carrots before adding them to the soup. Toss them with olive oil, salt, and pepper, and roast at 400°F (200°C) until tender and slightly caramelized. If you don't have vegetable bouillon, you can use vegetable broth instead. Adjust the amount of salt accordingly. A swirl of coconut milk or a dollop of vegan sour cream can add extra creaminess and richness to the finished soup. Garnish with toasted pumpkin seeds or a sprinkle of fresh herbs for added texture and visual appeal.