Take the onion rings in a bowl.
Squeeze the lime over them so that the juice seeps into the rings.
Follow it up by sprinkling the chaat masala over them.
Mingle properly so that the onions are completely layered with the masala.
Take a clean cutting board and arrange the bread slices over it.
First spread butter and then a generous layer of mint coriander chutney over each slice of bread.
Slice the leftover Chicken Tikka into small portions.
Cover the whole surface of two of the bread slices with these Tikka pieces.
Arrange as many onion rings on top of the chicken as you wish.
Cover up with another slice of bread.
You may even trim the sandwich edges if you desire.
The sandwiches can also be cut into halves and served.