Heat the olive oil in a large Dutch oven over medium-high heat. Add the onion, celery, carrots, potatoes, squash, sweet potatoes, and garlic and cook, stirring occasionally, until softened slightly, about five minutes.
Season with the turmeric, cumin, ginger, paprika, cinnamon, salt, and pepper. Cook and stir until well incorporated, about two minutes.
Add the green lentils and tomato paste, sauté for one to two minutes, and then add the vegetable stock.
Bring the soup to a boil, cover, and lower the heat so that it simmers for 20 minutes.
Stir in the red lentils, and cook for 10 more minutes.
Add the coconut milk, lemon juice, and spinach and cook, stirring, until the spinach has wilted, two to three minutes. Taste and season with more salt if you like.
Serve each bowl of soup with a drizzle of sour cream or chile oil, some parsley or cilantro, cracked black pepper, thin jalapeño slices, sea salt, or a wedge of lime (or all of the above; I’ve learned that presentation is everything!).
