Traditionally Nurungji was naturally made by cooking rice in a bapsot (rice pan) on a stove top, or wooden stove top. When rice was cooked, the bottom always somewhat burnt which was scraped off and dried or put water to make rice tea which usually drank after meal... You might have gone to a Korean restaurant and experienced nurungji when you eat a dol sot bibimbap (sizzling bibimbap); they'll give you hot water to add to the bowl to eat with the crispy rice at the bottom. You also get nurungji when you make bap (rice) using a nonstick pan, but this is a way to make a lot of nurungji at once.
2 cups of cooked white rice
1 cookie sheet, non-stick
Preheat oven to broil.
Spread cooked rice flat using wet wooden spatula on a cookie sheet, about l/8" thick. It’s easier to spread if the rice is warm; microwave 4-5 min if it’s cold rice.
Put cookie sheet in oven for 10 minutes and see if it’s browned at the bottom. Turn it over and leave it on for additional 10 min. If it’s not brown enough and crisp, leave it on for an additional min.
Let cool. Discard overly burnt pieces. You can store in a paper bag in the cup board – it will keep for a long time if it’s completely dried.
To eat, boil some water and add handful of nurungji and you will have sungnyung (roasted rice hot drink); eat it like a soup or just drink the water as tea.