01 -
Place the guajillo, ancho, and chile de árbol (if using) in a medium saucepan. Cover with water, bring to a boil, then reduce heat and simmer for 7 minutes until softened and pliable. Drain and let cool slightly before blending.
02 -
Transfer the softened chiles to a blender. Add the garlic, onion, tomatoes, cumin, oregano, and 1 cup of beef broth. Blend on high for about 60 seconds until completely smooth. Strain through a fine-mesh sieve for a silkier sauce if desired.
03 -
Pat the beef cubes dry with paper towels and season generously with salt and pepper. Heat the oil in a large Dutch oven or heavy pot over medium-high heat. Sear the beef in batches, without crowding the pan, for about 3 minutes per side until browned all over. Remove to a plate and set aside.
04 -
Pour the blended chile sauce into the same pot. Cook over medium heat, stirring frequently, for 5 to 6 minutes until the sauce darkens slightly and smells toasted and fragrant. This removes the raw edge from the blended chiles.
05 -
Return the seared beef to the pot and stir to coat with the sauce. Add the remaining cup of beef broth, bring to a gentle simmer, then cover and cook over low heat for 20 minutes.
06 -
Stir in the diced potatoes. Cover and continue simmering for 20 to 25 minutes, until the potatoes are fork-tender and the beef pulls apart easily. Taste and adjust salt and pepper.
07 -
Ladle the stew into bowls or spoon alongside rice. Garnish with chopped white onion, fresh cilantro, and sliced radishes. Serve with warm tortillas.