This Raspberry Pistachio Cake, prepared with homemade pistachio flour and packed with tart raspberries, is as much about simplicity as it is elegance! One layer, easy preparation, with simple garnishes. The flavor is reminiscent of classic French financier cakes. It makes a lovely afternoon tea or snacking cake, but can also be dressed with powdered sugar, additional berries, and a dollop of lightly sweetened whipped cream for a special occasion. While this cake is best served slightly warm out of the oven or the day it is baked, leftovers can be wrapped tightly in plastic wrap and stored at room temperature for 2 to 3 days.
Preheat the oven to 325°F (160°C) with a rack in the center position. Generously grease an 8-inch cake pan (at least 2-inches deep) with baking spray or butter and line the bottom with a round of parchment paper (here's an easy tutorial!), grease again, and set aside.
Make the Pistachio Flour: Place the shelled raw pistachios in a large food processor. Using the blade attachment, pulse repeatedly until finely ground and similar in texture to almond flour. Be careful not to over-process or the oils from the pistachios may release and the mixture can become clumpy.
Transfer the pistachio flour to a medium mixing bowl. Add the all purpose flour, baking powder, and salt and whisk thoroughly to combine. Set aside.
In a stand mixer bowl, combine the sugar and lemon zest. Using your fingertips, rub the lemon zest into the granulated sugar until fragrant and moist. Add the softened butter. Using the paddle attachment, cream the butter and sugar mixture over medium-high speed (6) until light and fluffy, about 3 to 4 minutes. Add the vanilla extract and beat until incorporated. Scrape down the bowl halfway as needed to ensure the ingredients are incorporated evenly. Reduce the speed to medium (4) and slowly add the eggs, one a time. Scrape down the sides of bowl as needed. Beat until incorporated (the mixture will look slightly broken). Over low speed, slowly add the flour mixture in two additions, alternating with the milk. The batter will come together. Scrape down the sides of the bowl with a spatula and gently mix the batter to ensure all of the ingredients are evenly incorporated.
Transfer roughly half of the batter to the greased, parchment-paper lined cake pan. Using a spatula, fold the raspberries into the remaining batter. The berries may break slightly, but that's fine. Transfer this batter to the cake pan, adding it directly on top of the first layer. Smooth the top of the batter with a small offset spatula. Sprinkle evenly with the turbinado (or Demerara) sugar. Why This Method Works: Dividing the batter and adding a portion (without raspberries) to the bottom of cake pan prevents the raspberries from sinking during baking.
Bake for 55 to 60 minutes, or until golden brown and a toothpick inserted in the center comes out clean. Allow the cake to cool in the pan on a wire rack for 10 to 15 minutes. Using a knife, run along the sides of the cake pan to release the sides of the cake and then carefully invert onto a wire rack. Flip and allow the cake to cool right-side up.
Serve slightly warm or at room temperature, dusted lightly with confectioner’s sugar as desired and additional fresh raspberries (optional).
Storage: While this cake is best served slightly warm out of the oven or the day it is baked, leftovers can be wrapped tightly in plastic wrap and stored at room temperature for 2 to 3 days.
Flavor Variation Ideas:
This cake can be adapted in so many ways! Substitute the pistachio flour with other nut flours, such as hazelnut or easy-to-findalmond flour. Use other berry varieties.
If using other nuts flours, add a touch of almond or hazelnut extract. Use orange zest in lieu or in addition to lemon zest. Garnish with finely crushed pistachios or sliced almonds for contrast and texture. It’s a wonderful canvas to get creative!