Caldillo duranguense

Place the Beef sirloin chunks in a large pot and cover with water. Add 75g of the White onion, 10g of the Garlic cloves, and 5g of Kosher salt. Bring to a boil, then reduce heat and simmer for 60-90 minutes, or until the Beef sirloin is very tender. Skim any foam that rises to the surface. Once cooked, remove the Beef sirloin, shred or dice it into bite-sized pieces, and set aside. Reserve 700ml of the cooking broth.

While the beef cooks, toast the Ancho chiles and Guajillo chiles in a dry pan over medium heat for 1-2 minutes per side, until fragrant but not burnt. Be careful not to burn them, as this will make the sauce bitter. Transfer the toasted Ancho chiles and Guajillo chiles to a bowl and cover with hot water. Let them rehydrate for 20 minutes.

Drain the rehydrated Ancho chiles and Guajillo chiles. In a blender, combine the rehydrated Ancho chiles, Guajillo chiles, Roma tomatoes, remaining 75g of White onion, and remaining 10g of Garlic cloves with 200ml of the reserved beef broth. Blend until very smooth. Strain the chile mixture through a fine-mesh sieve into a bowl, pressing down on the solids to extract as much liquid as possible. Discard the solids.