• Grind 125 grams of pistachios into flour using a blender or food processor. Do not grind for too long, or the fats will be released and a paste will form.

To make the pistachio cake:

• Mix the butter and white caster sugar until creamy. Add the eggs one at a time, adding the next egg only after the previous one has been fully incorporated. Add the vanilla extract with the last egg.
• Then, add the flour, baking powder, and pistachio flour. Season with a generous pinch of salt. Mix until you have a smooth batter. Stop mixing as soon as the last bit of flour has been incorporated.
• Pour the batter into a cake tin lined with parchment paper. Use a spatula to spread the batter evenly.
• Bake the cake for about 55 minutes at 180˚C/350°F with a conventional oven until golden brown.

White Chocolate Ganache and Decoration

• Chop the white chocolate into pieces and place them in a heatproof bowl with a small knob of butter. Heat the whipping cream in a saucepan over medium heat.
• As soon as the cream begins to bubble around the edges, pour it over the chocolate. Stir with a spatula until the chocolate has completely melted. Allow the ganache to cool to room temperature before pouring it over the cake.
• Meanwhile, coarsely chop the remaining pistachios and sprinkle them over the ganache.