In Bastani are little frozen pieces of cream and pistachio sticks hidden.
Mix the Cream: In a small bowl, mix the heavy cream with the powdered sugar until smooth.
Freeze: Pour the sweet cream mixture onto a baking tray in a very thin layer. Place it in the freezer until completely frozen solid.
Warm the Milk: Heat the whole milk with 1 teaspoon of the sugar in a saucepan. Be careful not to let it boil!
Remove from heat and let it cool slightly.
Whip the Yolks: In a separate mixing bowl, beat the egg yolks with the remaining sugar using a hand mixer until pale and fluffy.
Temper the Eggs: Slowly add the warm milk, a little at a time, into the egg yolk mixture while whisking constantly. Tempering the eggs this way prevents them from scrambling!
Thicken the Custard: Pour the mixture back into a saucepan over medium heat.
Stir continuously with a wooden spoon for about 5 minutes until the custard thickens and coats the back of the spoon. Remember: do not let it boil, or the eggs will curdle!
Infuse the Flavors: Remove from heat.
Dissolve the saffron threads in 1 teaspoon of hot water, then stir the golden saffron liquid and rosewater into the warm custard until combined.
Chill over an Ice Bath: Strain the warm mixture through a fine-mesh sieve into a clean bowl.
Prepare a larger bowl filled with cold water and ice cubes.
Set the bowl with the ice cream base inside the ice bath and whisk until cooled down completely.
Place the bowl with a lid into the freezer.
Over the next 3 hours, take the bowl out every 30 minutes and stir thoroughly to break up ice crystals before returning it to the freezer.