Soak the Beans: Begin by soaking the Anasazi beans overnight or for at least 6 hours in water. If you're short on time, use the quick-soak method by boiling the beans for 2 minutes, then letting them sit for 1 hour.
Sauté the Vegetables: In a large pot, sauté the chopped onion, garlic, carrots, and celery in a bit of olive oil over medium heat until softened.
Add Beans and Broth: Drain and rinse the soaked beans. Add them to the pot along with the vegetable broth, diced tomatoes (if using), cumin, paprika, and a pinch of salt and pepper.
Simmer: Bring the mixture to a boil, then reduce the heat to low. Let it simmer for 1 to 1.5 hours, stirring occasionally, until the beans are tender and the flavors are well combined.
Adjust Seasoning: Taste the soup and adjust the seasoning as needed. Add more salt, pepper, or spices to your liking.
Serve: Serve the soup hot with crusty bread or enjoy it as a standalone dish.