Prepare the dough: In a bowl, mash the boiled potatoes while they’re still warm.' Add the singhara flour, cumin seeds, chopped green chili, grated ginger, coriander powder, and a pinch of rock salt and black pepper.' Mix well.' Sprinkle a little water (or a teaspoon of ghee) and knead gently into a soft dough.' It should hold together but not be sticky – add more flour or water as needed.
Shape the patties: Divide the dough into small lemon-sized balls.' Flatten each ball slightly between your palms or on a piece of parchment to make mini flatbreads or tikkis about ¼–½ inch thick.' If the dough is very soft, dust your hands with a bit of singhada flour.
Cook until crisp: Heat a griddle (tava) or non-stick pan over medium-low heat.' Add a few drops of oil or ghee and spread it.' Place the patties on the hot pan and cook on each side for 2–3 minutes, pressing gently with a spatula so they make good contact with the heat.' They should turn golden brown and crispy.' (For a more indulgent version, you can deep-fry these patties in oil until they puff up – either way works, but roasting uses less oil.)
Spice and garnish: Arrange the cooked patties on a plate or shallow bowl.' Immediately squeeze fresh lemon juice over them and sprinkle a little more sendha namak and black pepper to taste.' Gently toss so the pieces absorb the seasonings.' Finally, sprinkle the chopped coriander leaves on top.' The result is a plate of golden, hearty chaat – each piece coated with zesty, peppery flavors and a hint of fresh herbs.
Serve hot: Serve this Singhada Chaat warm or at room temperature.' It makes a crunchy, satisfying snack or side dish. In a pinch, you can also break the larger patties into bite-size pieces and pile them like traditional chaat.