In a medium saucepan, combine the canned chili, garlic powder, and chili powder over medium heat.
Simmer the chili for 10 minutes, stirring occasionally, until heated through and slightly thickened.
Meanwhile, boil or grill the hot dogs according to package directions until heated through and slightly browned.
Toast the hot dog buns in a skillet or under the broiler for 1-2 minutes until lightly golden.
Place each hot dog in a bun, top generously with hot chili, and sprinkle with shredded cheese and diced onions.
Serve immediately while hot.