This soup is a classic throughout Mexico. Traditionally, stale corn tortillas are cut into thin strips, fried in oil, and then used to thicken a tomato-enriched broth. I use “oven-fried” corn tortilla strips, which are lighter and less messy to prepare. To make this soup especially hearty, I have added more onions and tomatoes than is customary in Mexico.

Steps

1. Move an oven rack to the middle position and heat the oven to 425 degrees. Place the tortillas on a rimmed baking sheet. Brush both sides of the tortillas with 1 tablespoon of the oil. Bake until lightly crisped, about 6 minutes. (Don’t let the tortillas become overly crisp and stiff, or they will shatter when you try to cut them into strips.) Cool the tortillas slightly and then use scissors to cut them into ½-inch wide strips. Set the strips aside.
2. Meanwhile, heat the remaining 2 tablespoons oil in a large saucepan over medium heat until shimmering. Add the onion and cook until golden, about 5 minutes. Stir in the garlic and chile and cook until softened, about 1 minute.
3. Add the tomatoes and broth, raise the heat to high, and bring to a boil. Stir in the tortilla strips and cilantro and cover the pan. Remove the pan from the heat and set aside until the tortillas soften and start to lose their shape, about 5 minutes. Adjust the seasonings, adding salt to taste.
4. Ladle the soup into bowls and serve, passing the lime wedges at the table.