Arisi upma is a very traditional tiffin in most brahmin homes. My mom makes yummy upma but I was not a big fan of that when I was young (though I eat it). But later I started missing it. This can be made in a jiffy if you have rice rava in hand. Else also just run in your blender and make rava. Some people add all the ingredients, take it to the miller to be ground to rava texture and store it. My mom has a different way to make this upma - she sprinkles water and soaks the rava, then runs in the blender a couple of times to make uniform sized rava. Today I enjoyed making and eating this upma with her. Here is her simple recipe for the great yet simple and tasty upma.
Mix well and add the rice rava. Stir continuously to avoid lumps.
Add salt and stir till all the water is absorbed. Lower the flame and cover and cook for another 5 to 10 min, till the rice is completely cooked and the upma comes out without sticking.
It should be fluffy and flaky. All done. Serve with chutney, sambhar, gothsu, or pickle.
Alternatively, to make this rava, all the ingredients can be mixed and rava can be made in a mill.