In a large skillet over medium heat, cook the ground beef and chopped onion until the beef is browned and the onion is softened, about 5-7 minutes. Drain any excess fat.
Add the minced garlic to the skillet and cook for 1 minute until fragrant.
Transfer the cooked beef mixture to the slow cooker.
Add the tomato sauce, kidney beans, chili powder, ground cumin, smoked paprika, salt, and black pepper to the slow cooker. Stir to combine.
Cover and cook on low for 6 hours, stirring occasionally if possible.
About 15 minutes before serving, place the hot dogs in the slow cooker to warm through.
To serve, place two hot dogs in each bun and spoon a generous amount of chili over the hot dogs.
Serve immediately.