Beef simmered in Oaxaca's yellow mole sauce with chiles, hierba santa, and masa-thickened broth. This protein-rich family dish showcases one of Oaxaca's seven legendary moles.
Place beef chuck roast in a large pot with 8 cups of water. Bring to a gentle simmer over medium heat, skimming off foam as needed. Cook, partially covered, for 1.5 hours until beef is tender.
Meanwhile, stem and deseed the guajillo and costeño amarillo chiles. Toast chiles in a dry skillet over medium-low heat for 1-2 minutes until aromatic, then soak in hot water for 10 minutes.
Blend soaked chiles with white onion, garlic cloves, tomatillos, black peppercorns, oregano, and cumin seeds with 1 cup of the beef broth until smooth.
Return strained chile puree to the pot with the beef. Add salt, simmer uncovered for another 40 minutes on low heat to develop flavor.
Mix masa harina with 1 cup warm broth to make a smooth slurry. Stir into pot along with potatoes, green beans, and hierba santa leaves. Simmer uncovered until vegetables are cooked through and sauce thickens, about 30 minutes.
Taste for seasoning, adjust salt if necessary, and serve mole amarillo hot, making sure each portion has beef, vegetables, and plenty of sauce.