Heat water and milk together in a pot and keep it aside.
Put instant pot on saute mode. Wait until the display shows HOT and add ghee or coconut oil. If using Indian style pressure cooker or a deep pot on a stove top, simply melt ghee/coconut oil on medium het.
Let the ghee or coconut oil melt and add lapsi, saffron, cinnamon stick, cloves and cardamom.
Roast lapsi until it turns golden brown and starts to form nutty smell, stirring it continually and making sure the color does not get too brown.
Once the lapsi is roasted, add hot water and hot milk to the pot. Be very careful while doing this step because there will be big splashes of hot liquid due to the hot pot if you try to add all at once. Slowly add little at a time.
Add sugar and cardamom powder. Stir well, bring it to boil. If using a pot on stovetop, skip adding sugar at this step, add it after all the lapsi is completely cooked in the the milk/water mixture.
Close the lid, secure the valve and cook it on high pressure for 20 minutes. Let the pressure release naturally all the way.
If using Indian Style Pressure Cooker, do 5 whistles and let the pressure release naturally all the way.