Heat the canola oil in a 5 quart nonstick saucepan over medium heat. Add the onions and garlic. Saute until soft, then add the bell peppers and chili powder. Cook until well blended, about 30 seconds. Add the black beans. Cook until warmed through, about 3 minutes. Add the tomatoes. Bring to a simmer and reduce heat. Cook until the chili thickens, about 15 minutes.
While the chili is simmering, in a medium saucepan, cover the hot dogs in water. Over medium heat, bring to a boil. Reduce heat to a simmer. Cook for 4 minutes or until heated through.
Remove 1 hot dog from the saucepan and place on 1 bun half. Top with 1/4 of the chili and 1/4 of the cheese. Repeat for remaining 3 hot dogs. Place hot dogs in the broiler for about 1 minute, or until cheese begins to melt. Serve hot.