Place oil in soup pot and heat over medium for 2 minutes. Add the onions, carrots, potatoes, and bell peppers and mix thoroughly. Cook over medium heat for 5 minutes, stirring occasionally. Add remaining ingredients, except tortilla strips and fresh cilantro, and bring to a boil. Reduce heat and simmer for 20 minutes. Adjust seasoning if necessary. Turn off heat and cover pot.

Fry tortilla strips in hot oil until crisp, and drain well on paper towels. Transfer soup to soup bowls, garnish with tortilla strips and fresh cilantro, and serve.