Henderson's Relish

Method

1. Peel and crush 1 garlic clove flat with the side of a knife, and finely grate 5 g of fresh ginger. Nothing needs chopping neatly - everything is strained out at the end.
2. In a small stainless steel or enamelled pan (never bare aluminium or cast iron, which the vinegar will attack), combine 175 ml of malt vinegar and 75 ml of water. Add 1 tbsp of tamarind paste, 1 tbsp of black treacle, 1 tbsp of dark brown sugar and 0.5 tsp of fine sea salt.
3. Add the crushed garlic and grated ginger, then whisk in 0.25 tsp of cayenne pepper, 0.13 tsp of ground cloves, 0.25 tsp of ground coriander and 0.25 tsp of ground black pepper. Whisk over a low heat until the treacle and sugar have fully dissolved and no grit remains on the base of the pan.