Wash the rice in running water and set aside.
Into the pressure cooker add 1-litre milk and the washed rice.
Set the pressure cooker and cook on a medium flame for 5 whistles.
You will need to watch out for the spillage through the pressure cooker as milk tends to bubble up. Lower the heat if the spillage comes about.
Once the whistles are done, remove from heat and release pressure naturally.
Now, stir and mash the rice with the back of a ladle. Add the rest of the milk and simmer and stir for 7 to 10 minutes till the milk bubbles and boils.
Add the cardamom powder, crushed rose petals and remove from heat.
The payasam is now ready to serve