Grate carrots. Heat milk to boiling and add the carrots. Cook until liquid is almost dried, stirring  to prevent sticking. Add ghee and cook more, stirring often to roast the carrots well (about ½ hour). Add powdered milk and sugar and cook until all the liquid is dried and the mass does not stick to the sides or on the pan. Add the nuts and raisins and turn off the heat. Serve hot with vanilla ice cream.