Roast the Aromatics: Heat an iron tawa (griddle) on the stove. Dry roast the peeled garlic, spicy green chillies, and mild green chillies until they develop light brown spots. Remove from heat and set aside.
Prepare the Papad: Add a few drops of oil to the tawa and lightly roast the urad dal papads. Once they cool down, use your hands to crush them into small, coarse pieces and keep them aside in a plate.
Make the Coarse Paste: Transfer the roasted garlic, roasted chillies, roasted peanuts, and fresh coriander leaves into a mixer jar. Pulse it just a few times to create a coarse, chunky mixture. Do not blend it into a smooth paste
Sauté the Onions: Heat the remaining oil in the tawa. Add the cumin seeds and let them splutter. Drop in the roughly chopped onion and sauté until it turns lightly golden.
Cook the Thecha: Add the coarsely ground chilli-peanut mixture to the onions. Stir continuously and sauté on a medium flame for about 2 minutes to cook off the raw flavours.
Add Salt and Papad: Lower the heat completely. Add a tiny pinch of salt (remembering the papads are salty). Add the crushed papad pieces to the tawa and mix everything thoroughly.
Final Toss: Sauté the mixture on low heat for 2 more minutes so the flavours combine beautifully. Turn off the stove. Your authentic Papad Thecha recipe is ready to serve!