Heat a pan on medium heat. Add semolina. Heat the semolina in the dry pan, stirring, until it has a pleasant smell and looks even drier. Transfer it to a bowl and set it aside.
In a clean frying pan, heated to medium heat, add ghee. Once it melts, add the mustard seeds. When they start to crackle, add the cumin seeds and lentils. Fry them, stirring, until they turn brown.
Add crushed cashew, chopped onion and cook until the onion becomes translucid.
Add the hot pepper, ginger, curry leaves and salt to taste.
Mix to incorporate and add two and a half cups of water. When the water boils, leave the heat on low and add the semolina, sprinkle small amounts at a time, stirring continuously.
When a thick pudding forms, put the lid on, turn off the heat and leave the pudding under the lid for 3-4 minutes before serving.
Place the Upma on plates and serve with fresh coriander and a squeeze of lime juice.