Cook the Beef:
Heat olive oil in a large pot or Dutch oven over medium-high heat. Add ground beef and cook until browned, breaking it apart with a spoon. Drain excess fat if needed.
Add Vegetables:
Add diced onion, green pepper, and garlic to the pot. Cook for 5–6 minutes until softened.
Season the Base:
Stir in chili powder, cumin, smoked paprika, oregano, cayenne pepper (if using), salt, and pepper. Cook for 1–2 minutes to release the flavors.
Add Tomatoes & Beans:
Stir in diced tomatoes, tomato paste, kidney beans, and beef broth. Mix well.
Simmer:
Bring the chili to a boil, then reduce heat to low. Cover and simmer for 45 minutes to 1 hour, stirring occasionally.
Adjust Seasoning:
Taste and adjust spices, salt, or pepper as needed.
Serve:
Ladle into bowls and top with cheese, sour cream, green onions, or other garnishes.