Pour the olive oil in a saucepan over medium-low heat. Add the garlic and stir for 1-2 minutes. Add the finely chopped onion and sauté until tender (about 4 minutes). Add the chopped celery and carrots and sauté for another 2-3 minutes.Pour into your slow cooker (I used a 6 quart crockpot) with the tomato, chicken, or vegetable broth, both cans of tomato sauce, and both cans of undrained diced tomatoes. Add in the drained and rinsed kidney beans, drained corn, and rinsed quinoa. (Wash your quinoa in a mesh strainer before using to remove the bitter saponin coating).Cover and cook on high for 3-4 hours or until the quinoa is cooked through and vegetables tender. At this time, add in the zucchinis and spinach along with fresh herbs, salt and pepper. I used a few tablespoons of finely chopped basil and 1 tablespoon finely chopped fresh oregano.Serve immediately.The longer you leave this in the slow cooker (or depending on different heats/types of slow cookers), the less soup-y it will be (the quinoa will take in more moisture) so watch the soup carefully and add more vegetable broth as desired.