Preheat your oven to 350°F / 175°C.
Grease an 8 or 9-inch round cake pan and line the bottom with parchment paper.
In a large mixing bowl, combine the ground pistachios, ground almonds, self-rising flour, baking soda, sugar, ground cardamom, and ground cinnamon.
Whisk until thoroughly combined.
Add the lemon zest, milk, and melted butter to the dry .
Mix until just combined.
Beat in the eggs one at a time, mixing well after each addition until the batter is smooth and fully incorporated.
Pour the batter into your prepared cake pan and spread it evenly.
Bake for 25 to 35 minutes, or until a wooden skewer inserted into the center comes out clean.
Let the cake cool in the pan for 10 minutes before inverting it onto a wire rack to cool completely.
While the cake cools, prepare the frosting.
Place the saffron threads in a small bowl with 1 tablespoon (15 ml / 0.5 fl oz) of just-boiled water.
Let it infuse for at least 10 minutes to release its color and flavor.
In a separate bowl, use an electric mixer to beat the softened butter and confectioners' sugar until the mixture is smooth, light, and fluffy.
Add the softened cream cheese and the saffron with its soaking liquid to the butter mixture.
Mix on low speed until just incorporated.
Do not overmix.
Chill the frosting in the fridge until you're ready to use it.
Once the cake is completely cool, spread the saffron cream frosting evenly over the top.
Garnish with the chopped pistachios and a sprinkle of edible flowers before serving.
Do not overmix the frosting once the cream cheese is added.
Mix only until it's just combined to keep it thick and spreadable.
