Rinse the rice under cold water to remove rice surface starch. Pour the rice in a bowl and cover it with warm water. Add 1 teaspoon salt and stir the rice with clean hands. Let the rice rest about 5 minutes in the warm water bowl.
Drain the rice with draining colander, which has extra-small holes so only the water drains not the rices. Wash with cold water again and drain well.
Melt the butter in a sauce pan until it starts to sizzle and add the risoni at medium-high heat. Stir until risoni changes its color from light to a bit dark color. Then add rice and stir 5 minutes.
Pour the 3 cups water into the pan and add the salt. Stir them and close the saucepan lid and turn the heat to lowest level.
Cook 12 minutes at lowest level heat. After it cooked, open the saucepan lid and put paper towel to the lid and close the lid again and let the pilaf rest for 5 minutes. After it rest, it will ready to serve.