Step 1: Heat olive oil in a large pot or Dutch oven over medium-high heat. Add ground beef and cook, breaking it apart with a spoon, until browned. Drain any excess grease.
Step 2: Add diced onion and bell peppers to the pot. Cook until softened, about 5-7 minutes.
Step 3: Stir in minced garlic, chili powder, cumin, oregano, smoked paprika, and cayenne pepper (if using). Cook for 1 minute more, stirring constantly, until fragrant.
Step 4: Pour in crushed tomatoes, diced tomatoes (undrained), and tomato paste. Stir well to combine.
Step 5: Add rinsed and drained kidney beans and black beans to the pot. Stir in beef broth, salt, and black pepper.
Step 6: Bring the chili to a simmer, then reduce heat to low, cover, and let it simmer for at least 30-45 minutes, stirring occasionally, to allow the flavors to meld. For a deeper flavor, simmer longer if desired.
Step 7: Taste and adjust seasonings as needed. Serve hot with your favorite toppings.