Melt the ghee or butter in a medium skillet over a medium heat. Add the grated pumpkin. Cook for a few minutes, stirring now and then until it has softened. Don't rush this bit; you should see it change color.  

Add the milk and stir it in so that it is absorbed. Then add the sugar and cardamom. Stir in and cook for a few minutes until glossy-looking but not wet. You can also make it more of a puree by adding a little more milk, covering and steaming a few minutes and then mashing before adding sugar etc. Serve it hot or chilled.