Wash and wipe-dry the apple. Cut it horizontally into half inch long slices.

Add sugar, vinegar, salt, turmeric, chili, cumin, coriander and mustard powder.

Keep aside.

To prepare tempering, heat oil in a wok and fry mustard and cumin seeds.

Add onion seeds and fenugreek seeds. Add ginger and garlic paste and after a few seconds, remove from heat and let it cool.

Pour the mixture over the apple.

Transfer it to a clean, dry airtight bottle.