You may wish to wear gloves to protect your hands. Roast the chiles.
Massage a small amount of oil onto exterior of peppers & either grill peppers or place on a cookie sheet & place under broiler of oven on the very top rack. Chiles should blister & blacken on the outside.
Rotate chiles as they roast so that they are evenly blackened.
Remove chiles from oven & place into a bowl.
Seal with plastic wrap & allow to rest for 15-20 mins.
After resting the chiles, pull the outer skin off of the chiles, as well as remove the bitter inner membrane & seed pods.
Cut chiles into small pieces & set aside.
Place oil in deep soup pot & allow to come to a very high heat.
Carefully place pork pieces in hot oil & allow to fry until browned on all sides, 4-6 mins.
Remove pork from pan, reduce heat to med-low & place onions & chiles into pan.
Allow onions to sweat & become translucent, 5-6 mins.
Place spices into pan & allow them to saute slightly, 1 min.
Add tomatoes to mixture, as well as stock, beans & pork.
Allow chili to simmer for 2 1/2- 3 hours at a low temperature.
Garnish with cilantro sprigs & baked tortilla strips or crushed tortilla chips.