Tacos de Barbacoa de Res

Begin by preparing the dried ancho chiles, dried guajillo chiles, and dried pasilla chiles. Remove the stems and seeds. Lightly toast the chiles in a dry pan over medium heat for 1-2 minutes until fragrant. Be careful not to burn them. Place the toasted chiles in a bowl and cover with hot water to rehydrate for 20-30 minutes.

While the chiles rehydrate, prepare the remaining sauce ingredients. Roughly chop 100g of the white onion and the garlic cloves. Peel the tomatillos.

Drain the rehydrated chiles. In a blender, combine the rehydrated chiles, tomatillos, garlic cloves, 100g of white onion, Mexican oregano, cumin seeds, black peppercorns, whole cloves, 1 bay leaf, apple cider vinegar, and 10g of fine sea salt. Add 200g of water. Blend until a smooth paste is formed, adding more water (up to 100g) if needed to achieve a pourable consistency.