Preheat and prepare the tin

• Preheat the oven to 180 °C.
• Line the baking dish with baking paper.

Make the pistachio batter

• Beat the butter with the sugar until pale and fluffy.
• Add the eggs one at a time, then the vanilla extract.
• Fold in the flour, ground pistachios, baking powder and salt, then loosen with the milk.

Bake the cake

• Pour the batter into the dish and smooth the top.
• Bake until golden and a skewer comes out clean.

Whip the pistachio frosting

• Beat the cream cheese with the powdered sugar.
• Fold in the remaining ground pistachios.

Frost and serve

• Let the cake cool completely.
• Spread the frosting over the top and cut into squares.