Roast the chickpea flour for about 5 minutes until it turns fragrant and nutty; do not brown.
Wash the baby potatoes and add them in boiling water. Cook until 50% done, drain and keep aside. Peel and halve them. You may choose to keep the peel on as well.
In a mixing bowl, add the yogurt, cooled chickpea flour, sumac, ginger garlic paste, chilli powder, black pepper and 1 tbsp oil.
Cover and marinate in the refrigerator for about 1 to 2 hours.
Remove 15 minutes before you are ready to cook the potatoes.
Heat a heavy-bottomed pan. I like to use a cast iron wok. Add 1-2 tbsp oil followed by the marinated potatoes.
Toss them around and let cook on a medium flame for about 15 minutes. Keep turning every now and then so that they get roasted evenly.
Once the potatoes have a good sear on all side, remove from the flame.
Transfer to a serving plate and serve hot immediately after garnishing with coriander leaves and a drizzle of some lime juice.