Gently rinse poha in a colander under running water 2-3 times until they soften and then drain out all the water. When you press with your fingers, it should break easily. Keep it aside.
Heat oil in a Kadai. Add raw peanuts and fry until they turn golden brown. Remove the peanuts to a plate and set them aside.
In the same kadai, add mustard and cumin seeds and let them splutter.
Then add green chilies, curry leaves, and chopped onion. Saute until onions turn soft and translucent.
Next, add cubed potatoes (or mixed vegetables) and cook for 2-3 minutes.Cover and cook on medium-low heat till the potatoes are soft and perfectly cooked. Sprinkle some water if required. (You can also use pre-boiled cubed potatoes to it and saute for 2 minutes). Add rinsed and drained poha, turmeric, salt, and sugar. Mix everything well.
If you feel the poha is too dry, sprinkle some water all over. Cover it with a lid and cook for 2 minutes on low heat.
Turn off the heat. Add the lemon juice and roasted peanuts, and give a quick mix. Garnish with coriander leaves.
Serve hot with Masala chai or Coffee.