Sopa Azteca (Sopa de Tortilla) — Mexican Crispy Tortilla Soup

Remove the stems from the chiles, slit them lengthwise and shake out the seeds; any seeds left behind can make the soup too hot. Heat a dry skillet over medium heat. Press the chiles in the pan with the insides facing down for 20–30 seconds, until fragrant, then remove them as soon as the aroma rises. Soak them in hot water until softened.

Place the whole tomatoes, unpeeled garlic cloves and halved onion in the same dry skillet. Char over medium-high heat, turning occasionally, until the skins are blackened in spots. This step gives the soup depth; boiled tomatoes will not have the same flavor.

Heat the olive oil in a wide pot and pour in the strained sauce all at once; it will splatter, so partially cover the pot with a lid. Cook over medium heat, stirring occasionally, until the color darkens and the sauce thickens to a paste-like consistency. In Mexican cooking this step is called frying the sauce; skipping it leaves a raw chile flavor.

Cut the tortillas in half, then into 5 mm-wide strips. Heat the oil to 175°C / 345°F; a strip should puff up and float as soon as you add it. Fry the strips in batches for 40–60 seconds, until golden. Lift them out with a slotted spoon, spread them on a wire rack and sprinkle with a pinch of salt.

Ladle the hot soup into warm bowls. Top with a handful of crispy tortilla strips, diced avocado, crumbled cheese and a spoonful of crema. Serve with lemon wedges on the side; the acidity cuts the sweetness of the chiles and balances the soup.