In a large skillet, heat a splash of oil over medium heat and add ground beef. Cook until browned, breaking it apart with a spatula, about 6-8 minutes. Drain excess fat and transfer meat to a slow cooker.

In the same skillet, add chopped onion and minced garlic, cooking for 2-3 minutes until softened. Add this mix to the slow cooker with the beef.

Add diced tomatoes and tomato sauce to the slow cooker, along with drained and rinsed kidney and pinto beans. Stir in chili powder, cumin, smoked paprika, and oregano.

If you prefer a thinner chili, add beef broth or water to achieve desired consistency. Stir well, cover, and cook on low for 6-8 hours or high for 3-4 hours.

Taste the chili before serving and adjust with salt and pepper as needed. Serve hot with your favorite toppings.