In a wide mixing bowl, take the whole wheat flour and salt. Mix well. Make a dent in the center and add water little by little. Gather the flour and knead into a soft, smooth dough. Lastly add 1/2 tbsp of oil and cover the dough. Set aside while preparing the stuffing.
In a pressure cooker, add the washed potatoes along with required water. Cook for 3 to 4 whistles until tender. Peel the skin and mash the potatoes thoroughly without any lumps using a potato masher. Mashing with zero lumps is crucial to prevent the stuffing from oozing out while rolling.
To the mashed potatoes, add ajwain, grated ginger, chopped green chilli, red chilli powder, garam masala, chaat masala, anardana or amchur powder, roasted cumin powder, chopped coriander leaves and required salt. Mix thoroughly to form a uniform stuffing mixture. Taste and adjust seasonings if needed.
Knead the dough again with lightly greased hands. Divide the dough into equal golf ball-sized portions. Divide the potato stuffing into balls of equal or slightly larger size than the dough balls.
Take an obbattu / plastic sheet lightly greased with oil. Place a dough ball on it and press into a small circle, keeping the edges slightly thinner than the center. Place a potato stuffing ball in the middle. Gather the edges of the dough over the stuffing, pinch tightly to seal and flatten gently.
Place another greased sheet over the stuffed ball and pat or roll gently into a round paratha of desired thickness (no dry flour dusting required in this sheet method). Alternatively, dust the stuffed ball generously with dry wheat flour and roll gently with a rolling pin on a flat board without pressing too hard.
Heat a heavy tawa on medium flame and drizzle a few drops of oil. Carefully transfer the rolled paratha onto the hot tawa. Cook on medium heat until golden brown spots appear on both sides, drizzling a little oil or ghee around the edges and over the surface. Remove and serve hot with chilled masala dahi raita or pickle!