Heat the olive oil in a large pot or Dutch oven over medium heat.
Add the diced onion and bell pepper to the pot. Sauté for about 5 minutes until they begin to soften.
Stir in the minced garlic and cook for an additional 1-2 minutes until fragrant.
Add the ground beef to the pot, breaking it up with a wooden spoon. Cook until browned, about 5-7 minutes. Drain any excess fat if necessary.
Stir in the chili powder, cumin, smoked paprika, salt, and pepper. Cook for another minute to toast the spices.
Add the kidney beans, black beans, diced tomatoes with their juices, and broth to the pot. Stir well to combine.
Bring the chili to a simmer. Reduce heat to low and cover. Let it cook for about 20 minutes, stirring occasionally.
Taste and adjust seasoning if needed. Serve hot, topped with optional garnishes like cheese, sour cream, avocado, or cilantro.