Heat the olive oil in a large skillet over medium-high heat. Add the ground beef, diced onion, and ¼ teaspoon kosher salt. Break the beef into crumbles and cook for 5–6 minutes, until no pink remains and the onion has softened.
Add the minced garlic and cook for another minute, stirring until fragrant. Drain any excess fat from the skillet.
In a medium bowl, whisk together the beef broth, tomato paste, halal-certified Worcestershire sauce, garlic powder, onion powder, smoked paprika, black pepper, and remaining 1 teaspoon salt until smooth.
Arrange the sliced potatoes across the bottom of a 6-quart slow cooker. Add the kidney beans and corn, followed by the browned beef and onion mixture.
Pour the prepared sauce evenly over the ingredients. Stir gently so everything is distributed without breaking the potato slices.
Cover and cook the Slow Cooker Cowboy Casserole on HIGH for 2–4 hours or LOW for 4–6 hours. The casserole is ready for the finishing ingredients when the potatoes are completely tender when pierced with a fork.
In a small bowl, combine the sour cream, 1 cup shredded cheddar, and hot sauce. Stir until well blended.
Gently fold the sour cream mixture into the casserole, taking care not to mash the tender potatoes.
Sprinkle the remaining ½ cup cheddar over the top. Cover and cook on HIGH for another 5–10 minutes, or until the cheese has melted.
Taste and adjust the salt, black pepper, and hot sauce as desired. Serve warm.