Add cashews to a mason jar or small bowl, cover in water, and let soak for overnight or at least 3-4 hours. In a rush? For a quick-soak method, soak the cashews in boiled water for 30 to 60 minutes. Drain and rinse the cashews.
In a high speed blender, blend together drained cashews and 1 cup of the vegetable broth. Blend until smooth and set aside.
In a large pot, heat the olive oil over medium heat. Add the minced garlic and diced onion and sauté for about 3-5 minutes, or until the onion is translucent. Season generously with sea salt and pepper.
Next, add the chopped carrots, bell pepper, sweet potato, celery, and diced tomatoes with their juices, the remaining 5 cups broth to the large pot. Add in seasonings. Stir well to combine. Bring mixture to a boil, reduce back down to medium-low. Season with additional salt and black pepper.
Let the soup simmer for abut 20 minutes uncovered, or until vegetables are tender. Stir occasionally. During the last 5 minutes of cooking, stir in the blended cashew & broth, spinach (or kale), and drained chickpeas. Add additional spices & seasonings if desired.
Enjoy immediately! Freezer-friendly: can freeze up to 6 weeks.