Heat a Dutch oven or large saute pan with oil over medium heat.
To heated oil, add onion and bell pepper. Cook, stirring frequently, until very tender, 6 to 8 minutes.
Add chipotle adobo sauce, chili powder, smoked paprika, cumin, salt, and garlic powder and stir gently until spices are fragrant, about 2 minutes.
Add kidney beans, black beans, lentils, tomato sauce, and stock.
Bring to a simmer. Simmer, stirring occasionally, for 20 minutes to let the flavors come together.
Taste finished chili and add some more salt, if needed.
Ladle chili into bowls. Serve with toppings and chips.