Heat olive oil in a skillet over medium heat.

Add the chopped onions and garlic to the skillet.

Cook, stirring, until the onions and garlic are soft and translucent (about 5 minutes).

Add the lean ground beef to the skillet, breaking it up with a spoon.

Cook until the beef is nicely browned (about 10 more minutes).

Stir in the ketchup, crushed tomatoes, chili powder, and yellow mustard.

Simmer for 15 minutes until the chili has thickened.

Season the chili with salt and pepper to taste.

Boil, fry, or grill the hot dogs until cooked through.

Serve each hot dog in a bun.

Top with the prepared chili.

Add chopped onions, chopped tomatoes, and shredded cheddar cheese to each chili dog.