1 tbsp sunflower oil
1 tsp each black mustard seeds and cumin seeds
½ white cabbage, finely shredded or coarsely grated
1 red onion, finely sliced
1 green chilli, chopped (optional)
½ lemon, juiced
Heat the oil in a frying pan and warm the mustard and cumin seeds until they sizzle and crackle, then remove from the heat. Combine everything together in a mixing bowl with a large pinch of salt and serve. Can be made a day ahead and kept in the fridge.