Chop the White Onion (2) and Garlic (3 clove).
In a dry pan on medium high heat, toast the Dried Pasilla Chile Pepper (2), flipping occasionally. Once fragrant, add Water (1 cup) to the pan. Bring water to a low boil. Cook until dried pasilla chilis are soft. Remove, drain, and cut off tops.
In a blender, thoroughly blend chilis with Tomato (14.5 ounce) until no chunks remain.
Heat some Oil (to taste) in a soup pot, then add onions and garlic. Cook until golden. Heat Chicken Stock (4 cup) in a separate pot, then add Chicken Breast (1). Cover pot and cook on medium-low heat until cooked through, 20-25 minutes.
Add tomato mixture to onions, turn up heat, and let reduce by half. Season with Salt (to taste) and Ground Black Pepper (to taste).
Once chicken breast is done poaching, shred meat with a fork and knife. Add to the tomato mixture along with the Canned White Beans (2 cup) and chicken stock. Add Salt (to taste), and mix well. Bring to a boil, and simmer 15 minutes.
To serve, add some Tortilla Chips (to taste), Feta Cheese (to taste), Avocado (1), squeeze of a Lime (1), and Fresh Cilantro (1 handful).