Directions
<ol class="no-list-style"><li class="MethodStepper"><h4 class="step-title">Step 1</h4>Preheat your oven to 170°C (340°F). Grease and line three 20cm round cake tins with baking parchment. In a food processor, pulse 150g of the pistachios until finely ground, being careful not to over-process into a paste. Set aside.</li><li class="MethodStepper"><h4 class="step-title">Step 2</h4>In a medium bowl, whisk together the flour, baking powder, and salt. Set aside. In the bowl of a stand mixer fitted with the paddle attachment, cream the butter and sugar for 5-7 minutes until very pale and fluffy. This extended creaming creates air pockets that will help your cake rise evenly and have a tender crumb.</li><li class="MethodStepper"><h4 class="step-title">Step 3</h4>Add the eggs one at a time, beating well after each addition. If the mixture looks curdled, don't worry - it will come together when you add the dry ingredients. Mix in the vanilla, almond, and pistachio extracts (if using).</li><li class="MethodStepper"><h4 class="step-title">Step 4</h4>With the mixer on low speed, add 1/3 of the flour mixture, then half the milk, another 1/3 of flour, remaining milk, and finally the last of the flour. Mix just until combined, being careful not to overmix (which develops gluten and makes cakes tough). Fold in the ground pistachios and a few drops of green food coloring if using.</li><li class="MethodStepper"><h4 class="step-title">Step 5</h4>Divide the batter evenly between the prepared tins. Use a kitchen scale for perfect layers - each tin should contain about 450-500g of batter. Gently tap the tins on the counter to remove air bubbles. Bake for 25-30 minutes until a toothpick inserted in the center comes out clean and the cakes spring back when lightly touched.</li><li class="MethodStepper"><h4 class="step-title">Step 6</h4>Allow the cakes to cool in the tins for 10 minutes before turning out onto a wire rack to cool completely. For the best texture and easy frosting, wrap the cooled cakes in plastic wrap and refrigerate for at least 2 hours or overnight. Cold cakes are much easier to frost without crumbs.</li><li class="MethodStepper"><h4 class="step-title">Step 7</h4>For the Swiss meringue buttercream, place egg whites and sugar in a heatproof bowl set over a pot of simmering water (not touching the water). Whisk constantly until the mixture reaches 71°C (160°F) and the sugar has completely dissolved (rub a bit between your fingers to check - it shouldn't feel grainy).</li><li class="MethodStepper"><h4 class="step-title">Step 8</h4>Transfer the mixture to a stand mixer fitted with the whisk attachment. Beat on high speed until stiff, glossy peaks form and the bowl feels cool to the touch, about 10 minutes. This cooling is crucial - adding butter to warm meringue will result in a soupy mess.</li><li class="MethodStepper"><h4 class="step-title">Step 9</h4>Switch to the paddle attachment and add the butter a few cubes at a time, mixing well after each addition. The buttercream might look curdled at some point - keep beating, it will come together! Once smooth, add the vanilla, salt, and finely ground remaining pistachios (50g). Beat until fully incorporated.</li><li class="MethodStepper"><h4 class="step-title">Step 10</h4>To assemble, place one cake layer on a serving plate or cake stand. Spread about 1 cup of buttercream evenly over the top. Place the second layer on top and repeat. Add the final cake layer. Apply a thin crumb coat of buttercream over the entire cake and refrigerate for 20 minutes to set.</li><li class="MethodStepper"><h4 class="step-title">Step 11</h4>Apply the final coat of buttercream, smoothing with an offset spatula. Press the remaining roughly chopped pistachios around the bottom edge of the cake and sprinkle some on top for decoration. For the best flavor, let the cake sit at room temperature for 1-2 hours before serving, allowing the flavors to fully develop.</li><li class="MethodStepper"><h4 class="step-title">Step 12</h4>The cake will keep at room temperature in a cake keeper for up to 3 days, or refrigerated for up to a week. If refrigerated, allow slices to come to room temperature before serving for the best flavor and texture. The nutty pistachio flavor actually improves on the second day!</li></ol>