Heat the oil over medium heat in a dutch oven or large heavy-bottomed pot. Add the red pepper, onion and jalapeno and saute until softened, about 5-10 mins.
Stir in the reserved beans, salsa, cumin and season generously with kosher salt and pepper. Simmer until hot, about 15 mins. Thin with additional stock if necessary.
Recipe Notes:
I use vegetable stock to keep this dish vegetarian, but chicken stock can be substituted.
Pureeing the beans and sautéed veggies make this soup thick and hearty.