Heat a skillet over medium heat. Add the ground beef and cook, breaking it up as it goes, until browned, about 5-6 minutes. Drain excess fat.
Add the chopped onion and cook until softened and translucent, about 3-4 minutes.
Stir in the tomato sauce, tomato paste, chili powder, cumin, garlic powder, paprika, salt, pepper, and broth until well combined.
Reduce the heat to low and simmer, stirring occasionally, for 15-20 minutes, until the chili is thick enough to mound on a spoon. If it gets too thick, stir in a splash more broth.
To assemble the chili dogs:
While the chili simmers, cook the hot dogs to your liking. Grilling over medium-high for 5-7 minutes gives the best char, though boiling, pan-frying, or baking all work.
Toast the buns, then place a hot dog in each and spoon a generous amount of warm chili over the top.
Add your favorite toppings and serve right away, while everything is hot.
Notes
Use 85% lean beef: Enough fat for flavor without leaving the chili greasy.
Simmer until thick: The chili should mound on a spoon so it clings to the dog instead of soaking the bun.
Skip the beans: Keeping it fine and bean-free lets it spread evenly over the dog.
Char the dogs: Grill or pan-sear for a smoky, snappy exterior.
Toast the buns: A toasted bun holds up better under a loaded dog.
Add cheese under the chili: A thin layer melts into the bun and guards against sogginess.
Store separately: Keep the chili, dogs, and buns apart in airtight containers for 3-4 days.
Make the chili ahead: It doubles easily and reheats well, so cook it a day ahead and warm it up when you're ready to build.