Drain and wash the soaked chickpeas.
Add fresh water and salt and pressure cook the chickpeas for 3-4 whistles till they are soft.
Cool completely.
In a bowl add the chickpeas, chopped onions, tomatoes, green chillies, potatoes, coriander leaves, chaat masala, lemon juice and salt.
Mix everything well. At last add cheese if you like.
Serve!!