In a sauce pan combine the chopped onion, garlic and the rest of the ingredients. Bring to a boil, reduce the heat to medium/medium-high and simmer for 30 minutes stirring occasionally.
Pour the thickened sauce through a mesh strainer that has been placed into a large bowl to catch the onions and garlic, use a spoon or spatula to press the sauce through. Wipe any excess off the bottom of the strainer and into the bowl.
Let the steak sauce cool before transferring to an airtight container and into the fridge.
Can be stored in the fridge for two to four weeks.