
Combine the raisins and ¼ cup water. Set aside and let the raisins soak for 15 minutes.
Heat the olive oil in a small skillet over medium low heat. Add the onion and cook for 3-5 minutes until softened. Stir in the garlic, ginger paste and anchovy paste and cook for 1 minute.
Transfer the onion mixture to a blender. Add the raisin/water mixture, apple cider vinegar, and molasses. Blend until smooth.
Pour the mixture into medium saucepan. Whisk in remaining ½ cup water, tamarind paste, fish sauce, soy sauce, black pepper, dry mustard, cardamom, cinnamon, cloves and cayenne.
Bring to a simmer over medium low heat. Simmer for 5-8 minutes.
Remove from the heat. Put a lid onto the saucepan and leave to steep and cool for 1 hour.
Strain the mixture through a fine mesh sieve. Store in an airtight jar or container in the refrigerator for up to 3 months.