Toasting on the comal: the technique that awakens the flavour of chillies and seeds

What is it?

Toasting on the comal is the ancient Mexican technique of heating dried chillies, seeds, spices, nuts, tortillas and other ingredients on a comal —a flat clay or iron disc— at medium-high temperature without fat, until they release aromas, brown lightly and develop deep flavours. The comal (from the Nahuatl 'comalli') is the pre-Hispanic utensil par excellence of Mexican cuisine, the basis for making tortillas, roasting, toasting and keeping food warm. The toasting technique is applied especially to prepare mole pastes, salsas, marinades, atoles and all kinds of preparations where one seeks to concentrate and shade flavours. Unlike tatemado (where partial charring is sought), toasting is controlled: one seeks to brown without burning, since burning seeds and spices produces irreversible bitterness. It is a key technique in the traditional kitchens of central, southern and southeastern Mexico.

Origin and history

The comal is a fundamental pre-Hispanic utensil in Mesoamerican cooking for more than 3,500 years. The oldest known comales are round pieces of fired clay found at Olmec, Mayan and Mexica sites, described in the 16th-century Florentine Codex of Fray Bernardino de Sahagun. They were the centre of the domestic hearth along with the three tenamastles (stones that held it over the fire), where cooking went on all day. The toasting technique developed alongside the comal: toasting dried chillies to soften their skin, toasting pumpkin seeds (pepita), sesame, peanuts and chocolate to release aromatic oils, toasting whole spices to activate volatile compounds. According to Larousse Cocina, traditional toasting uses clay comales from Atzompa, Oaxaca or Comonfort, Guanajuato, which provide a subtle mineral flavour. Wrought iron comales became popular in the 20th century. Today they coexist with industrial griddles in restaurants and with domestic frying pans in urban kitchens. Mexico Desconocido documents the comal as the 'heart of Mexican cuisine', present in indigenous, rural and urban kitchens, from humble homes to Michelin-starred restaurants.

Characteristic ingredients

Toasting on the comal has specific variants according to the ingredient. For whole dried chillies (ancho, mulato, pasilla, guajillo, chipotle): they are deveined and placed on a dry comal over medium heat, turning them constantly for 30 to 60 seconds until they crackle slightly and release aroma; they should not darken too much (burn) because they will turn bitter. They are then hydrated in hot water for 15 minutes. For seeds (pumpkin seed, sesame, peanut, almond): they are placed on a dry comal over medium-low heat and stirred constantly with a wooden spoon until lightly and uniformly browned, 5 to 8 minutes. For whole spices (clove, pepper, cinnamon, cumin, aniseed): they are briefly toasted for 30 to 60 seconds on a dry comal until they release aromas. For tortillas: they are heated on the comal over medium heat for 30 seconds per side to soften them, or longer to make them crunchy (totopos). For grains such as cacao: they are toasted whole on the comal until they release aroma and the shells crack, before being peeled and ground. For leaves (epazote, hoja santa): they are briefly toasted to concentrate flavour. The ideal comal temperature is 180 to 200 degrees Celsius; too hot, the ingredients burn; too cold, the flavours do not develop.

Cultural significance

Toasting on the comal is a fundamental technique of traditional Mexican cuisine and forms part of the UNESCO inscription of traditional Mexican cuisine in 2010. The comal is one of the most identifying symbols of Mexican cuisine, comparable to the Asian wok or the European bread oven. Contemporary cuisine has revalued artisanal comales: potters from Atzompa, Comonfort, Capula, Mata Ortiz and other regions produce premium comales sold in gourmet markets and restaurants. The precise toasting of chillies for mole is a skill passed from generation to generation among traditional cooks, especially in Oaxaca, Puebla, Tlaxcala and Mexico City. Cooks such as Abigail Mendoza, Margarita Carrillo Arronte and Edelmira Linares have documented and taught the technique. The clay comal has also been reclaimed by chefs such as Enrique Olvera, Jorge Vallejo and Daniela Soto-Innes in their premium restaurants, where toasting on the comal provides a unique flavour impossible to match with electric or induction griddles. The conservation of traditional comal pottery is a cultural-ecological cause: it protects an ancient craft and cooking techniques that do not pollute or require electricity.

Frequently asked questions

What is the difference between toasting and tatemar?

Toasting is controlled: the ingredient is heated on a dry comal until lightly browned without burning, seeking to develop flavour without charring. Tatemar involves partially burning the skin of the chilli or vegetable until it has black spots, with pronounced smoky flavour. Toasting is applied to seeds, spices and dried chillies where burning would ruin the flavour; tatemado is applied to fresh chillies and vegetables such as tomatoes and onions.

Why are dried chillies toasted before use?

Brief toasting on a dry comal serves several functions: 1) It softens the skin so that it hydrates better in hot water. 2) It activates volatile aromatic compounds that give depth of flavour. 3) It reduces the raw herb sensation. 4) It concentrates the natural sugars for light caramelisation. 5) It improves the final texture of the salsa or mole. It is an obligatory step in any traditional mole, marinade or sauce made from dried chillies.

What type of comal is best?

Traditional glazed clay comales (Atzompa, Comonfort, Capula) provide a subtle mineral flavour and distribute heat evenly, but they are fragile. Wrought iron comales are durable, harness heat well and improve with use (they 'season' like a cast-iron pan). Industrial griddles and non-stick pans work but without the flavour of clay or iron. Each traditional Mexican kitchen usually has several comales for different uses.

Where do the comal and toasting come from?

It is of Mesoamerican origin, with more than 3,500 years of documented antiquity. It was the central utensil of the Aztec, Mayan, Zapotec and practically all Mesoamerican peoples' domestic hearth. The word comes from the Nahuatl 'comalli'. After the conquest, the Spanish adopted the comal and the toasting technique, which survive in all traditional Mexican, Central American and southwestern American cuisine to this day.