In a large stock pot or Dutch oven, warm the oil over medium heat until shimmering. Add the fennel seeds and let them toast, stirring, for 30 seconds or until fragrant.
Add chopped onions, garlic, celery, mushrooms, and cauliflower. Sauté over medium-high until tender and lightly golden (about 8-10 minutes). Add salt, pepper, oregano, and red pepper flakes.
Add carrots, rinsed beans, canned tomatoes, 4 cups water mixed with 2 tablespoons Better than Bouillon, quinoa/lentils and kale to the pot and stir to combine. Partially cover (crack the lid) and let the soup simmer over medium-low for 15-20 minutes until the grains are tender. Add the additional 2 cups water as needed for thinning.
Taste and adjust seasonings. Add a sprinkle of nutritional yeast (optional) for extra depth of flavor (could sub in a tablespoonful of soy sauce instead - also optional). Swirl in the vegan heavy cream or cashew cream (if using). If you like creamy vegetable soup, see options below in recipe notes.
Top each bowl of vegetable soup with a squeeze of lime juice, a dollop of cashew cream or sour cream, a handful of parmesan cheese, chopped fresh herbs or hot pepper flakes. Enjoy with homemade dinner rolls or vegan cornbread.