Caldo de queso sonorense: the creamy soup with potato and green chilli

What is it?

Caldo de queso is one of the most representative soups of Sonora, a northern state with a tradition of cattle and cheese-making. Its base is a broth of potato diced into cubes, roasted tomato, onion, garlic and Anaheim green chilli (also called northern green chilli). What distinguishes it is the final addition of regional cheese, ranchero, asadero or cocido, cut into cubes that partly melt on contact with the hot broth, together with whole milk or crema to give the characteristic milky colour. It is served very hot with freshly made Sonoran flour tortillas. Although humble in ingredients, it is an identity dish of the state, part of family menus and fondas in Hermosillo, Caborca, Magdalena and Ciudad Obregon. Animal Gourmet, Los Sabores de Mexico and El Sol de Hermosillo document it as one of the icons of Sonoran cuisine, alongside grilled meat, bacanora and coyota.

Origin and history

Sonoran caldo de queso was born at the rural Sonoran table at the end of the 19th century and the beginning of the 20th, in an area where bovine cattle-raising brought an abundance of milk and fresh cheese, and where European potato was intensively grown in the Sonoran valleys. El Sol de Hermosillo documents that the dish became popular at the ranches of central and northern parts of the state as a restorative supper after the day's work in the fields. The combination of boiled potato, fresh cheese and green chilli reflects the binational heritage with Arizona and New Mexico, where similar dishes such as 'green chile stew' exist. However, the Sonoran version is distinguished by the use of regional cheese, ranchero or asadero, and by the Sonoran flour tortilla as a compulsory accompaniment. The recipe does not appear in colonial books or in 19th-century national publications: it is a rural-cuisine dish codified orally and spread through Sonoran migrants, especially in Phoenix, Tucson and Los Angeles. Animal Gourmet records testimonies of Sonoran cooks who attest that caldo de queso was a typical dish of Lent and vigil, when meat was replaced by cheese.

Characteristic ingredients

The potato used is the white or alpha variety, cut into medium cubes so it keeps its shape. The guaje tomato is roasted until charred on a dry comal or frying pan, then blended with garlic and strained. The Anaheim green chilli, long, of mild to moderate heat, bright green colour, is roasted, peeled, deseeded and cut into strips or cubes. White onion is finely sliced and softened in oil or lard. The tomato broth is poured over the onions, chicken stock or water is added, the potatoes are added and the dish is cooked until soft, about 20 minutes. At the end whole milk or Mexican crema, the chilli cubes and the cubes of Sonoran ranchero, asadero or cocido cheese are added. The cheese must be added once the heat is off so it partly melts without falling apart. Some versions include chopped coriander at the end, or a touch of Sonoran oregano. The broth must not boil after adding the cheese to prevent it from curdling. It is served immediately with hot flour tortillas.

Cultural significance

Caldo de queso is one of the gastronomic symbols of Sonora, integrated into its regional identity alongside grilled meat, chiltepin, coyota and the cuisine of the Yaqui and Mayo peoples. The Sonora Ministry of Tourism includes it in its official gastronomic catalogue and in tourist routes as 'essential when visiting the state'. It is mainly eaten with family and at local fondas as lunch or a light supper, especially during winter when temperatures in central Sonora fall considerably. The dish is also common during Lent as a meatless option. The 2010 UNESCO inscription of traditional Mexican cuisine focuses on Michoacan, but the northern corpus, caldo de queso, machaca, gallina pinta, is part of the regional diversity that enriches it. The Sonoran cheese industry, especially the dairies of Caborca, Magdalena and Ures, benefits from the continuous consumption of this dish. Chefs such as Aaron Sanchez and Pati Jinich have included versions of caldo de queso in their books and television programmes as an example of northern cuisine.

Frequently asked questions

What is the difference between Sonoran caldo de queso and queso fundido?

Sonoran caldo de queso is a brothy soup of potato, tomato and green chilli to which cubes of cheese are added at the end. Queso fundido (or queso flameado in Tex-Mex) is a dry dish of cheese completely melted in a clay pot with chorizo or rajas. One is eaten with a spoon as a soup; the other is eaten with tortillas as a fondue or cheese for tacos.

What does caldo de queso taste like?

It tastes of boiled potato with sweet roasted tomato, slightly spicy Anaheim green chilli and a creamy background of cheese melted with milk or crema. The ranchero cheese contributes mild lactic acidity, and the softened onion sweetness. It is a comforting soup, creamy but not heavy, with moderate heat from the chilli. The hot flour tortilla completes the northern profile.

How is caldo de queso served?

It is served very hot in a deep bowl, with the potatoes, the partly melted cubes of cheese and the creamy broth. It is obligatorily accompanied with freshly made Sonoran flour tortillas to lift the cheese. Some diners add lime, chiltepin salsa or chopped coriander. It is a single dish or accompanied with charro beans for a complete Sonoran table.

Where is caldo de queso originally from?

It is native to Sonora, particularly central and northern parts of the state: Hermosillo, Caborca, Magdalena, Ures. It was born at Sonoran ranches at the end of the 19th and beginning of the 20th century, taking advantage of the abundance of regional fresh cheese and potatoes grown in the valleys. It is related to the green chile stews of the US Southwest, the result of shared border culture.