Heat the vegetable oil in a large pot over medium heat. Add the diced onion and green bell pepper, stirring occasionally until they soften, about 5 minutes.

Stir in the minced garlic and sauté for an additional 1 minute until fragrant.

Increase the heat to medium-high and add the ground beef and ground pork. Cook until browned and no pink remains, about 5-7 minutes.

If there's excess fat, carefully drain it while leaving some for flavor.

Sprinkle in the chili powder, ground cumin, paprika, dried oregano, and cayenne pepper. Stir for about 1 minute to toast the spices.

Pour in the diced tomatoes, tomato sauce, beef broth, and brown sugar. Stir until well combined.

Bring to a gentle simmer, reduce heat to low, cover, and let simmer for 30 minutes, stirring occasionally.

Stir in the drained kidney beans and simmer for an additional 15 minutes.

Taste and adjust salt and black pepper as needed.