In a large pot or Dutch oven, heat olive oil over medium heat.
Add the diced onion and green bell pepper. Sauté for about 5-7 minutes, until softened.
Add minced garlic and sauté for another 1-2 minutes until fragrant.
Cook the meat:
Add the ground beef to the pot. Cook until browned, breaking it up with a spoon as it cooks. Drain any excess fat.
Combine the ingredients:
Stir in the chili powder, cumin, paprika, oregano, cayenne pepper, salt, and black pepper. Cook for another 1-2 minutes to let the spices become fragrant.
Add the diced tomatoes, tomato sauce, tomato paste, and beef broth. Stir well to combine.
Add the kidney beans and black beans. Stir to combine all ingredients.
Simmer the chili:
Bring the chili to a boil, then reduce the heat to low. Cover and let it simmer for at least 1 hour, stirring occasionally.
The longer you let it simmer, the more the flavors will develop. If you have time, let it simmer for 2-3 hours.
Adjust seasoning:
Taste the chili and adjust the seasoning as needed. Add more salt, pepper, or spices to taste.
Serve:
Serve the chili hot with your favorite toppings. Enjoy with a side of cornbread or over rice if desired.