In a saucepan, whisk together milk and flour.
Once the mixture is well homogenized, add the cardamom capsules slightly open.
Whisk continuously while heating the mixture over medium heat. It should begin to thicken after about ten minutes. If the mixture reaches boiling point, lower the heat.
When the mixture starts to thicken, add the sugar, mix well, and continue cooking for 4 minutes, then lower the heat to minimum. You can taste the mixture to adjust the amount of sugar to your taste!
Add 1 tsp of rose water and 1 tsp of orange blossom, stir with the whisk, and stop cooking after 2 minutes.
Pour into small ramekins, let cool and put in the refrigerator for at least two hours (or overnight).
Just before serving, dilute a little honey with rose water and orange blossom and pour over the blancmange. Finely chop the pistachios and sprinkle over them.