Prepare vegetables by chopping onion, carrots, celery, and zucchini. Mince garlic.
For the soup, heat the 2 tablespoons olive oil in a large pot over medium heat. Add the onion, garlic, carrots, and celery. Season with salt and pepper. Cook, stirring occasionally, until carrots are tender, about 7 minutes. Stir in the cumin and coriander. Add the 28 ounces crushed tomatoes, vegetable stock, and zucchini. Bring to a low simmer and stir in the quinoa. Simmer uncovered until the quinoa is cooked, 10 to 15 minutes, stirring occasionally. Season to taste with salt and pepper.
For the tortilla strips, preheat the oven to 425°F. Cut the tortillas into 1/8-inch strips, drizzle with 1 tablespoon of olive oil, and sprinkle with salt. Toast on a cookie sheet, turning once, until golden, about 5 minutes.
Place the tortilla strips, diced avocados, cilantro, cheese, sour cream, and lime wedges in individual bowls and offer as toppings.