Salvadoran fermented cabbage relish (Curtido)

1. Quarter the cabbage, cut out the core and slice into thin strips; grate the carrot and slice the onion into thin half-moons.

2. Put the vegetables in a large bowl, pour boiling water over them (not the 250 ml in the recipe – just enough to cover), leave for 1 minute, then drain – this softens them slightly so the flavour penetrates more easily.

3. Mix the vegetables with the Mexican oregano, chilli flakes and salt.

4. Pack tightly into a clean jar.

5. Mix the cider vinegar with the 250 ml of cold water and pour over the vegetables to cover completely; seal and leave at room temperature for 1-3 days, then refrigerate.

6. Serve cold with pupusas – but it's also great with roast meat and tacos.

Tip: Curtido is the inseparable partner of pupusas: in every pupusería in El Salvador it stands on the table in big jars and everyone takes as much as they like – it keeps 2 weeks in the fridge.