Mix all the ingredients except the cornstarch in a thick-bottomed pan. Turn the heat on to medium.
Meanwhile, in a separate small bowl, mix the cornstarch with 1 teaspoon water. Add this mixture to the chutney.
Once the chutney starts boiling, turn the heat off. Turning the heat off after the first boil will ensure that the cornstarch imparts a slight thickness to the chutney. (We do not want the chutney turning into a paste.)
Once the chutney cools down, store in the refrigerator in a clean glass bottle.
Serving Suggestion: Add 2 teaspoons chutney to a cup of crispy rice cereal. Mix a pinch of salt and red chile powder, a spoonful of diced red onions, and chopped cilantro for a quick snack. Or enjoy with aloo chaat.