01 -
Heat olive oil in a large pot over medium heat. Add chopped onion and cook for 5 minutes, stirring occasionally, until soft and fragrant.
02 -
Add minced garlic, ground cumin, salt, and pepper. Stir constantly for 1 minute to allow spices to release their essential oils and deepen in flavor.
03 -
Add diced tomatoes with green chiles, black beans, pinto beans with liquid, and tomato paste if using. Pour in 4 cups of broth, bring to a boil, then reduce heat and simmer uncovered for 15 minutes.
04 -
Remove 1/2 cup of bean mixture, mash with a fork, and return to pot. Add cooked rice, corn if using, and half the cilantro. Simmer for 5 minutes, adjusting with more broth if needed.
05 -
Taste and adjust seasoning with salt, pepper, or cumin as needed. Warm tortillas in skillet or microwave, then wrap in foil to keep warm.
06 -
Ladle soup into bowls, sprinkle with shredded cheddar and remaining cilantro. Serve hot with warm tortillas on the side.