Prepare the beef. Trim off visible fat and tough silverskin. Slice the meat thinly across the grain, then chop into small pieces.
Cook the tomatillos and green chiles. Place the tomatillos, serranos, and jalapeños in a saucepan and cover with water. Simmer approximately 5–7 minutes, until softened and the tomatillos turn olive green. Drain and let cool slightly.
Blend the salsa. Blend the cooked tomatillos, serranos, and jalapeños with the white onion, garlic, cilantro, 1/8 teaspoon cumin, 1 teaspoon Mexican oregano, about 1/2 teaspoon salt, and 1 cup of the measured chicken broth until smooth.
Brown the bacon. Cook the bacon in a large, heavy pot over medium heat until browned. Remove and reserve, leaving approximately 3 tablespoons of bacon fat in the pot.
Fry the onions and chiles güeros. Add the Mexican grilling onions and whole chiles güeros to the bacon fat. Cook, turning occasionally, until browned and softened. Remove and reserve.
Cook the beef. Season the chopped beef to taste with the garlic, salt, and pepper seasoning mix. Add it to the pot and stir until it changes color. Cover and cook over medium-low heat for 5–10 minutes, stirring occasionally, until it releases its juices. Keep those juices in the pot.
Add the salsa and broth. Stir in the blended salsa and remaining 2–3 cups broth. Bring to a gentle simmer and add about 1/2 teaspoon chicken bouillon. Cover and cook until the beef is tender. Start checking after 45 minutes; chuck may need more time. Add more hot broth as needed if the liquid reduces too much.
Finish. Return half the bacon. Simmer another 10 minutes, then taste and season with chicken bouillon as needed.
Serve. Spoon warm beans into each bowl, then ladle in the beef and broth. Finish with the reserved crispy bacon, chopped onion, cilantro, lime, and radishes. Serve with warm tortillas. Add the reserved Mexican grilling onions and chiles güeros to each bowl.