Greengage chutney

1 tbsp of vegetable oil

100ml of white wine vinegar

1 onion, finely diced

1/4 large green chilli, deseeded and finely diced

300g of greengage plums, washed, halved and stones removed

1 tomato, finely diced

1 knob of ginger, peeled and grated

1/4 tsp turmeric powder

1/2 tsp mustard seeds

2 cardamom pods, crushed and outer husk discarded

1 tbsp of sugar, (optional)

salt