1Soak the dried mushrooms in hot water for 20 minutes. Drain and reserve. If the mushrooms are in very large pieces, cut them in half.
2In a deep soup pot, heat the oil over medium-high heat, add the onion and sauté 3 minutes. Add the garlic and continue cooking for 5 minutes more. Add the fresh mushrooms and sauté until softened and lightly browned, about 5 minutes.
3Add the drained, dried mushrooms. Tie the epazote, thyme, oregano and rosemary sprigs in a bundle with kitchen string and add to the pot. Add the chiles and the broth. Stir and bring to a boil. Reduce heat and simmer for about 1 hour.
4Remove the herb bundle and salt to taste. Garnish with lime wedges or fresh epazote.
From south of the border comes this spicy and hearty soup ladled over crisp tortilla strips and grated cheddar. The soup is chunky with chicken and avocado, but it's the tortillas that give it a slight thickness and a special flavor.