Methods

1. Preheat oven to 350°F and grease a 9 x 13-inch cake pan. Set aside.
2. In a large bowl, sift together the flour, baking powder, baking soda, salt and milk powder.
3. In a separate large mixing bowl, cream the butter and granulated sugar together until it is nice and fluffy, about 3 minutes. Add the eggs one by one, mixing in between additions. Add the vanilla and mix for 30 seconds. Make sure to scrape down the sides of the bowl every once in a while. Add the dry ingredients to wet ingredients in three additions, mixing in between each addition. Pour the batter into the prepared baking pan and spread evenly. Bake for 25-30 minutes and cool completely. Use a fork to poke a bunch of holes into the cooled cake. 
4. Make the soaking milk for the cake - in a small saucepan, add the steeped saffron milk and cardamom. Bring to a boil while stirring continuously over medium heat. Boil for 2 minutes. Pour the hot milk into a medium mixing bowl. Add the heavy cream, sweetened condensed milk, evaporated milk and rose water. Whisk well. Refrigerate until ready to use. 
5. When the cake is completely cool, pour the milk mixture over the cake. It will look like a lot of liquid, but the cake will soak it all up. Place the cake in the refrigerator. Refrigerate the cake until you make the whipped cream. You can also store the cake in the fridge overnight and top it with whipped cream the next day when you're ready to serve it.
6. To make the whipped cream, pour the heavy cream and vanilla into a mixing bowl. Whisk the cream mixture until you have stiff peaks. You can spread the whipped cream on top of the cake with a spatula or pipe it on with a piping bag. Sprinkle the top with chopped pistachios.