Take 4 slices of bread and apply butter on one side of each slice.
Grate 200 grams of cheese (preferably a mix of mozzarella and cheddar) and set aside.
Finely chop 1 small onion, 1 small tomato, and 1 small capsicum. Mix them in a bowl and add salt, black pepper, and 1/2 teaspoon of chaat masala to taste.
Place a non-stick pan on medium heat. Put one slice of bread with the buttered side facing down on the pan.
Spread a generous layer of the grated cheese on the bread slice, followed by a layer of the chopped vegetable mixture.
Place another slice of bread on top, with the buttered side facing up.
Cook the sandwich for 2-3 minutes on each side or until the bread turns golden brown and the cheese melts.
Repeat the process for the remaining bread slices to make another sandwich.
Cut the sandwiches into halves or quarters and serve hot with ketchup or chutney.