Take 3 leftover rotis and, using a bowl, cut round shapes from each roti.
Now make small slits from the edge toward the center and arrange the rotis inside tea sieves.
Heat oil. Place the tea sieve in the oil and press the roti gently with a spoon. Fry until it becomes crispy. (Refer to the video.) Prepare all the katoris in the same way.
In a mixing bowl, add 1 cup boiled and chopped potatoes, ½ cup boiled chana, ½ cup chopped onion, ½ cup chopped tomatoes, some coriander leaves, salt, 1 tsp red chilli powder, 1 tsp chaat masala, and 1 tsp lemon juice. Mix well. The stuffing for the katori is ready. Keep it aside.
In another bowl, take ½ cup curd and 2 tbsp powdered sugar. Mix well. The sweet curd is ready.
For serving, take a roti katori and add the stuffing. Top it with sweet curd, chaat masala, green chutney, sweet tamarind chutney, sev, and pomegranate seeds.
Roti Katori Chaat is ready. Serve immediately.