Step 1

Measure out 7 cups of milk.

Step 2

Heat 2 cups of the milk in a 6-Qt non-stick pan on medium heat, and bring it to a low boil, about 5 minutes. Use a silicone covered whisk to stir a few times to keep the milk from sticking and burning.

Step 3

Meanwhile, in a small bowl whisk together the rice flour with ⅔ cup cold water until smooth and without lumps.

Step 4

Reduce the heat to medium low and add the rice flour mixture into the hot milk and whisk with vigorous, constant motion until the mixture thickens and a few air pockets start bursting on the surface, about 5 minutes. Continue stirring with a whisk for another 2-3 minutes.

Step 5

Add 1 cup of the cold milk and continue whisking over medium low heat until it thickens again and a few air pockets burst on the surface. This will take about 7-10 minutes.

Step 6

Add the 4th cup of milk and whisk until it thickens but not bubbling. Add the sugar and rose water. Continue whisking over medium low until it thickens and a few air pockets burst on the surface.

Step 7

Increase the heat to medium and add the remaining 3 cups of cold milk one cup at a time and whisk until thickened with air pockets forming, before adding the next cup of milk. Each cup of cold milk will take 7-10 minutes to thicken over medium heat. Continue to whisk to prevent the custard from sticking to the pot.

Step 8

After the last cup of milk thickens and air pockets start bursting on the surface, whisk gently but continuously and simmer for another 3-5 minutes.

Step 9

The mixture will have a thin custard consistency and will thicken further as it cools.

Step 10

Pour the custard in 7 serving bowls immediately. Sprinkle the top with chopped pistachios and refrigerate uncovered for at least 2-3 hours to set before serving. Cover the chilled custard bowls tightly with a plastic wrap and store in the refrigerator for up to 3 days.