Steps
1. In a medium pot, heat olive oil over medium heat.
2. Add the diced carrot, celery, and sliced leek. Sauté for about 5 minutes, until softened.
3. Stir in the diced butternut squash and rinsed red lentils; cook for another 2 minutes.
4. Pour in the vegetable broth and bring to a boil. Reduce heat and let it simmer for 20 minutes, or until the squash and lentils are tender.
5. Remove from heat and stir in the miso paste until fully dissolved.
6. Use an immersion blender to puree the soup until smooth (or blend in batches).
7. Season with salt and pepper to taste. Serve hot, garnished with fresh herbs if desired.