Rinse the hog plums with enough water and pat dry them using a kitchen towel. Scrape the pulp along with skin and discard the fibrous seed from hog plums.
Add all the scraped pulp, green chillies and salt to the mixer jar. Grind them together coarsely without adding any water.
Next heat a pan adding oil, mustard seeds, split black gram lentils and curry leaves. As the mustard seeds start spluttering include the ground hog plum mix. Cook it in medium flame with constant strring. When the mixture turns thick and most moisture evaporates then switch off the flame.
Tangy, spicy hog plum chutney is ready to relish with steamed rice topped with ghee.
Notes
Do not grind the hog plum too finely. The coarse chutney tastes better.
Use enough oil in seasoning and cook till most of the moisture evaporates. This helps in extending the life of chutney.
Hog plum chutney can last for a week at room temperature and more if refrigerated.