In a dry pan over low heat, roast the sesame seeds, Timur peppercorns (or Sherwani chillies), and dried red chillies until fragrant. Transfer to a mortar and pestle (or spice grinder) and grind coarsely; set aside.

Heat the mustard oil in the same pan. Add the fenugreek seeds and let them sizzle for a few seconds.

Stir in the sliced onions, chopped garlic, and julienned ginger. Sauté on medium heat until the onions soften and begin to brown.

Add the roasted spice mix, roasted cumin powder, chaat masala and salt.

Toss in the boiled potato cubes, chopped green chillies, and lemon juice. Mix gently so that the potatoes are evenly coated in the spiced oil.

Remove from heat and fold in the chopped coriander leaves. Transfer to a serving bowl.