Cook oatmeal in salted water about 5 minutes. Put madzoon in a large bowl and pour oatmeal mixture gradually in the madzoon so it won't curdle. Pour back into pan and put on low fire to keep warm. Melt the butter and fry the onions in it, add chopped mint leaves, then pour over the soup. This delicious soup can be prepared in about 8 minutes.
Variation - This same soup can be made with shehrieh ( fine noodles) in place of the oatmeal. Use 3/4 cup of shehrieh.