In a bowl, combine all-purpose flour, salt, and oil. Mix well.
Gradually add water and knead into a soft dough. Cover and let it rest for 15 minutes.
Heat oil in a pan and sauté sprouted mung beans for a minute.
Add red chili powder, turmeric, cumin, coriander powder, salt, and a squeeze of lemon. Mix and sauté for 1–2 minutes. Avoid overcooking to retain the crunchiness of the sprouts.
After resting, knead the dough again until soft. Divide into small dough balls.
Sprinkle flour on a rolling surface and roll each dough ball like a roti. Prick lightly with a fork.
Place a small steel or metal bowl in the center of the rolled dough. Wrap the dough around the bowl and trim the edges.
Fry the dough-wrapped katori in medium-hot oil along with the bowl. Carefully remove the bowl and continue frying until golden and crisp. Repeat for all katories. Let them cool.
To assemble Katori Chaat, place sprouts in the crispy katori as a base.
Add boiled potatoes, green chutney, sweet chutney, and yogurt. Sprinkle red chili powder and chaat masala.
Top with chopped onions, tomatoes, additional chutneys, fine sev, and coriander.
Serve immediately and enjoy with friends and family.