Coney Island Hot Dogs

1 ½ pounds lean ground beef
1 white onion, diced
⅓ cup ketchup
2 tablespoons butter
2 cloves garlic, crushed
2 tablespoons chili powder, or more to taste
Kosher salt and fresh-ground pepper, to taste
1 teaspoon ground cumin, or to taste
1 teaspoon celery salt, or to taste
1 pinch cayenne pepper, or to taste
8 good quality, all-beef hot dogs
8 good quality hot dog buns
Prepared yellow mustard
Combine ground beef, water, 1/2 cup diced onion, ketchup, butter, garlic, chili powder, salt, black pepper, cumin, celery salt, and cayenne pepper together in a pot. Mix with a potato masher or spatula over medium-high heat until mixture has a finely ground testure and begins to bubble, about 10 minutes.
Bring beef mixture to a simmer, reduce heat to medium-low, and cook, stirring occasionally, until sauce thickens and reduces, about 1 hour. Season with salt and pepper to taste.
Bring a large pot of water to a boil. Cook hot dogs in boiling water until heated through, 5 to 7 minutes.
Preheat the oven to 350 degrees. Arrange hot dog buns on a baking sheet. Cook buns in the preheated oven until soft and warm, 2 to 3 minutes.
Place 1 bun on a plate. Place a hot dog in the bun and top with meat sauce. Drizzle yellow mustard and a portion of remaining diced onion over the meat sauce. Repeat with remaining hot dogs.
Enjoy!