In a large Dutch oven, heat olive oil over medium-high. Add onion and garlic. Cook, stirring often, until vegetables soften, about 5 minutes.
Add diced chicken thighs. Toss it in the pot and season with salt and pepper. Cook about 5 minutes.
Toss in chipotle in adobo sauce and dried oregano and stir until aromatic, about 2 minutes.
Add red bell peppers and corn; season. Cook, stirring often, adding a teaspoon or two of oil if they start sticking, until softened, about 5 minutes.
Pour in chicken stock. Add diced fire-roasted tomatoes. Bring to a boil; reduce heat to medium. Cook, stirring often, until slightly reduced, about 15 minutes.
Rinse 1 to 3 cans black beans. Cook, stirring often, until flavors meld, about 15 minutes.