Blend the rice with half a cup of milk until the rice looks like pearls; do not make it into a paste, as this is a very important part of this recipe.
Heat a pan on medium-low and add 2 tablespoons of water, ensuring the surface of the pan is wet. Add the blended rice, milk, thinly sliced patha, and almond powder. Increase the heat to medium-high, bring the milk to a boil, then lower the heat to medium-low. Cook for about 15 minutes, stirring occasionally and cleaning the sides to prevent the milk from burning.
Add sugar and cardamom and cook for a few more minutes. Remember, as the kheer (pudding) comes to room temperature, it will thicken slightly. If needed, add a bit more milk and bring it to a boil once more. At this point, you can also adjust the sugar.
The kheer is ready. Serve it chilled and garnish with sliced pistachios.