In a skillet, fry Chipotle peppers over low heat, stirring frequently. The heat will open up the flavor of the chilies a bit. Be careful not to burn them, to avoid bitterness.
Transfer the roasted Chipotle peppers into a bowl and pour in water to rehydrate them. Let soak for 15 minutes. Once rehydrated and softened, remove the peppers from the bowl and set aside. Keep the rehydration water! Coarsely slice the chilies.
Peel and chop onion.
In a medium saucepan, drizzle vegetable oil. Fry onions until translucent. Add Worcestershire sauce, preserved water and rehydrated chilies, ketchup and all remaining ingredients.
Bring to a low boil, stirring occasionally for 5 minutes.
Pour contents of saucepan into a blender or use a hand blender to puree until smooth and creamy
