In a medium bowl, add all the ingredients except the crackers, and the sev. Taste for seasonings and just before serving, add the crackers, puffed rice, or popcorn.
Garnish the finished chaat with drizzles of chutney.
Instead of goldfish crackers, you can substitute puffed rice, cheesy popcorn, bhel mix, or even your favorite cheese crackers. Priya calls for Parle cheeselings, so certainly use them if you can find them.
If using a granny smith apple instead of the green mango, rub the juice of half the lemon over the apple pieces to prevent browning.
Ifyou are not a big fan of raw onions, place the chopped onions in a small bowl and cover with cider vinegar and marinate for at least 15 minutes or more. Alternatively, you could use scallions instead.
This is not a dish that you can make and leave out for hours. The crackers and sev will go soggy if not eaten pretty quickly.