Cook ground beef and onion in a large skillet, over medium-high heat, stirring frequently, until meat is browned.
Add chili powder or cumin.
Add enough water to just cover meat.
Reduce heat, cover and simmer 1 hour.
Season to taste with salt.
Stir in bread crumbs, a little at a time, until a serving consistency is reached.
(Mixture should just begin to hold together, but still be fairly soupy.) Serve meat on buns.
Time preparation: 5 min.
Time total: 75 min.