Place the rice in a medium-sized bowl. Fill the bowl with cold water and swirl the rice around to help remove the starch.
Carefully pour off the water, making sure not to pour out the rice that has settled to the bottom. Repeat this step 7-8 times, or until the water is clear.
Fill the bowl with enough cold water to cover the rice by 2 inches. Let the rice soak for 30 minutes.
Drain the rice and set aside.
Place the milk in a 6-8- quart pan over medium heat, uncovered, and bring to a boil. This will take about 10-12 minutes. Watch it carefully so it does not boil over, and stir frequently to prevent scorching.
Add the drained rice. Return it to a boil. This will take 1-2 minutes.
Reduce to a simmer and cook, uncovered, for 30-35 minutes. The rice will absorb the milk as it cooks and thickens. Stir frequently, occasionally mashing the rice with a whisk.
If the rice sticks, lower the heat.
After almost all the milk has been absorbed and the rice is very tender, add the sugar and ground cardamom. Stir well to combine all the ingredients.
Pour the rice into a heat-proof bowl. Let it cool for 10-15 minutes. Cover and chill completely.
When ready to serve, spoon the chilled dessert into individual serving dishes and garnish with the pistachios, raisins, and sliced almonds.