In a small saucepan over medium-high heat, combine the water, tomatillos, serrano peppers, and garlic. Bring to a boil, cover, and simmer for 10 minutes. Take the food off the stove and let it cool. Place all ingredients in a blender, blend until smooth, and reserve. (If you prefer, you may omit the simmering phase and simply combine the raw tomatillos, peppers, and garlic with little water and a little browned flank beef.)

Cook and stir flank steak in a hot, nonstick skillet over medium-high heat until it is thoroughly browned. Put the steak in the tomatillo mixture and heat to a boil. Heat should be reduced to medium after adding the chicken bouillon. For 30 to 1 hour, cook the meat in a covered skillet until soft.

In the meantime, reheat pinto beans in a pot over medium heat; then, turn down the heat to low to maintain warmth.

Mixture of flank steak, pinto beans, and bacon is then divided among 6 dishes. Each dish should be topped with a lime wedge, onion, cilantro, and black pepper.