Heat oil in a large pot or Dutch oven over medium heat. Add diced onion and bell pepper. Sauté for 5-6 minutes until softened and edges begin to brown.
1 medium onion, 1 bell pepper, 2 tablespoons oil
Add minced garlic, chili powder, and ground cumin to the pot. Stir constantly for 1-2 minutes until fragrant and spices evenly coat the vegetables.
3 cloves garlic, 2 tablespoons chili powder, 1 tablespoon ground cumin
Pour in drained and rinsed black beans, kidney beans, and pinto beans, followed by diced tomatoes with their juice and vegetable broth. Stir to combine.
1 can (15 oz) black beans, 1 can (15 oz) kidney beans, 1 can (15 oz) pinto beans, 1 can (28 oz) diced tomatoes, 2 cups vegetable broth
Bring chili to a boil over high heat. Once boiling, reduce heat to low and partially cover the pot. Simmer gently for 40 minutes, stirring every 5 minutes to prevent sticking and scorching.
Remove the lid completely and simmer uncovered for the final 10 minutes to thicken the sauce through evaporation. Taste and adjust salt, pepper, and chili powder seasoning as desired before serving.
1 teaspoon salt, 0.5 teaspoon black pepper, 2 tablespoons chili powder
