Heat a pan and add the oil. When the oil is hot, add the mustard seed and cumin seeds. Let the mustard seeds and cumin seeds sizzle. And then, add the onions and cook until the onions are soft and translucent.
Now add the salt and cook for 30 seconds. Then reduce the heat to low and add the cooked rice and the kothamalli powder.
Gently mix, make sure there aren't any lumps, and mix the spice powder evenly. Serve with raita or any poriyal/dry curry of your choice.
Adjust the spice and salt to your taste.
Swap white rice with grains of your choice.
Onions are optional. You can also add nuts for added crunch.