In a large pot, heat the oil over medium-high heat. Add the onions and cook, stirring, for 4 minutes. Add the garlic and cook, stirring, for 1 minute. Add the ketchup, brown sugar, cane syrup, vinegar, mustard, Worcestershire, hot sauce, Essence, and red pepper flakes and bring to a boil. Lower the heat and simmer, stirring occasionally, until thickened and the flavors marry, 15 to 20 minutes. Remove from the heat and let cool slightly before serving.
Yield: about 4 cups