2Place the cleaned Tripitas de res in a large pot, cover with water, add 50g of Cebolla blanca, 10g of Ajo, and 5g of Sal. Bring to a boil, then reduce heat and simmer for 2 to 3 hours, or until the Tripitas de res are very tender. Drain and let cool slightly, then dice them into small, uniform pieces (approximately 1-2 cm).
3Remove stems and seeds from the Chile guajillo and Chile ancho. Place them in a small pot with enough water to cover, bring to a boil, then remove from heat and let them rehydrate for 15 minutes.