In a large skillet over medium heat, brown the ground beef along with the diced onion and minced garlic for about 5–7 minutes. Drain excess fat and transfer to slow cooker.

Add kidney beans and black beans to the slow cooker. Pour in crushed tomatoes and diced tomatoes, stir to combine.

Mix in tomato paste and beef broth, stirring until all ingredients are combined.

Sprinkle in chili powder, ground cumin, smoked paprika, salt, black pepper, and oregano. Stir to evenly distribute the spices.

Cover the slow cooker and set to LOW for 6–8 hours or HIGH for 3–4 hours until bubbling and ingredients are tender.

Once cooked, stir chili and serve hot with optional toppings such as shredded cheese, sour cream, or sliced green onions.