Combine the raisins and 1/4 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 and apple cider vinegar. Blend until smooth.

Pour the mixture into a medium saucepan. Whisk in the remaining 1/2 cup water, 2 tbsp tamarind paste, 1 tbsp fish sauce, 2 tbsp soy sauce, 1 tsp black pepper, 1 tsp dry mustard, 1/2 tsp cardamom, 1/4 tsp cinnamon, 1/8 tsp cloves, and a pinch of cayenne pepper.

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.