In a large bowl, season lamb all over with salt and pepper.

In a large pot, heat oil over medium heat.

Working in batches, add lamb and cook about 2 minutes per side, until browned.

Transfer lamb to a large plate as done. Discard excess fat, leaving only about 1 tablespoon in the pot.

Bring pot back to medium heat, add green bell peppers, Poblano or Anaheim pepper (if using), red bell peppers, and onions and cook for about 5 minutes, scraping bottom from time to time to get all the browned bits of meat folded in with the vegetables.

Add jalapeño and cook for another 3 minutes, stirring from time to time.

Add garlic, cook for 1 minute more, then add chile powder, oregano, coriander, cumin, and salt and pepper.

Let spices cook, stirring constantly, for 1 minute.

Return lamb to pot. Stir in broth, Worcestershire sauce, sugar, tomatoes, chipotle sauce, and bay leaf.

Raise heat and bring to a boil. Once boiling, taste sauce and adjust salt and pepper.

Lower heat to a slow simmer, cover and cook for about 30 minutes.

Check on the consistency of the sauce and add water 1/2 cup water at a time to reach desired thickness.

Add beans and continue simmering, covered, for another 10 minutes or until beans are warmed through.

Ladle chili into bowls and garnish with green onions and chopped cilantro.

Recipe Variation: To add a smoky depth of flavor, you can roast the Poblano or Anaheim pepper before adding. Using tongs, hold the pepper over a high heat gas flame, charring all over for about five minutes. You want the pepper skin to have a very dark color on all sides. When done, place in an airtight container and let stand to "sweat" for about 5 minutes. Using plastic gloves to protect your fingers, rub the skin off and discard. Open the pepper and remove veins and seeds and discard the top or stem. Chop and add to recipe along with the jalapeño pepper.