Wash and dry ½ kg lemons. Cut the lemons in 4 pieces.
Add 1 cup white vinegar, ½ cup sugar, 10 green chilies, 1 tsp nigella seeds, 1 tbsp white cumin, 1 tbsp turmeric, 2 tbsp red chili powder, 2 tbsp black mustard seeds, and salt.
Mix all ingredients well and leave it for half an hour.
Heat 1 cup oil in a pan, cook marinated lemons for 5 minutes and wait for it to cool.