Heat the olive oil in a large skillet over medium heat.
Add the diced yellow onion, red bell pepper, and minced garlic to the skillet and sauté until the vegetables are softened.
Add the ground beef to the skillet, breaking it into small crumbles with a wooden spoon, and cook until fully browned.
Transfer the beef and vegetable mixture into a slow cooker.
Add the black beans, tomato puree, chili powder, smoked paprika, cumin, sea salt, and black pepper to the slow cooker.
Stir all ingredients until well combined.
Cover and cook on low for 6 hours or on high for 3 hours to allow the flavors to deepen.
Ladle the hot chili into a bowl and serve immediately.