Cut the lemons into small pieces. Peel and finely chop the ginger and garlic. Heat the oil to medium heat in a small saucepan and add the mustard seeds. When they start to pop, add the ginger and garlic, and stir for 30 seconds. Add the rest of the spices and fry 20 seconds more. Add the water, vinegar, sugar and lemons, bring to the boil and simmer for 15-20 minutes, stirring occasionally. Leave to cool.
«This pickle will keep very well, particularly if you place in a sterilised jar while still hot.»