Place the chicken breast in a medium saucepan, fill with water and bring to a boil. Boil the chicken breasts over medium heat until they are completely cooked, about 35 minutes. Remove the pan from the heat and remove the chicken breast to a separate plate so they can cool more quickly.

Once the chicken breasts are cool, remove the skin and bones. Shred or chop the chicken. Discard the bones and skin, and the leftover chicken broth can be used in another dish.

Meanwhile, place the dried chile ancho in a saucepan half-filled with water and bring to a boil. Lower the heat, and simmer for about 10 minutes, until the chiles are tender. Drain the water and remove the stems and seeds. Rinse away any extra seeds. Discard the stems, water and seeds.

Place the prepared chiles in the container of a blender and add the water, garlic and season with salt. Puree the chiles well.

Heat the vegetable oil in a medium sized skillet. Add the pureed chile sauce and saute for 2-3 minutes. Add the shredded cooked chicken and toss to combine with the sauce. Cook over a low flame for about 5 minutes. If the sauce reduces too much and the dish seems dry, add a spoonful of the leftover chicken broth or water.