New York-Style Hot Dog Onions
This is an easy version of the traditional hot dog topping that's served by New York City street vendors.
Heat oil in a large skillet over medium heat. Add onions; cook and stir occasionally until the onions are slightly browned and somewhat soft, about 10 minutes. Stir in the ketchup, brown sugar, chili powder, hot sauce and cinnamon; mix well. Add the water and bring mixture to a boil; simmer, uncovered, until onions are completely tender and the liquid is mostly evaporated, an additional 10 minutes.