In a medium Dutch oven, saute the onion in 1 tablespoon of olive oil over medium heat until translucent, about 5 minutes. Add the garlic and the cumin, and saute for another 2 minutes until fragrant.Add the salsa to the pot along with the veggie stock and the salt. Bring to a boil. Stir in the rice and the beans. Turn the heat down to medium-low, cover and cook for 35-40 minutes, until the rice is tender. Stir in the corn and the cilantro, and taste for seasoning. Stir in half of the crushed tortilla chips.Ladle the soup into bowls or mugs, and top with the remaining tortilla chips, lime wedges, avocado and cheese (if using). Enjoy!