Preheat broiler, with rack 3 inches from heat source. Arrange tomatoes, jalapeno, onion, and garlic, cut side down, on a rimmed baking sheet. Broil until starting to char, about 5 minutes. Pulse tomatoes and jalapeno in a blender or a food processor until chunky. Chop onion and mince garlic.
Heat a large heavy skillet (preferably enamel cast-iron) over medium-high heat. Add oil. Working in batches, brown chicken in a single layer, allowing to sear before stirring, 5 to 6 minutes; transfer to a plate.
Reduce heat to medium. Add onion and garlic to skillet. Cook until soft and golden, about 8 minutes. Add chili powder and 2 teaspoons salt. Cook, stirring, for 1 minute. Stir in chipotles, and add chicken. Raise heat to high. Add tomato-jalapeno mixture. Cook, scraping up browned bits, until fully incorporated, 3 to 5 minutes. Stir in stock; simmer for 20 minutes. Add beans; simmer for 10 minutes. Serve with desired toppings.