- 3/4 cup whole blanched almonds
- 2/3 cup plus 1/2 cup unsalted pistachios (about 7 ounces)
- 6 tablespoons unsalted butter, softened
- 1 1/4 cups sugar
- 4 large eggs
- 1 tablespoon finely grated lemon zest
- 1 tablespoon fresh lemon juice
- 1 vanilla bean, halved lengthwise and seeds scraped
- 1/4 cup plus 2 tablespoons extra-virgin olive oil
- 2/3 cup all-purpose flour
- 1/4 teaspoon salt
- Finely grated zest of 1 lemon
- Juice of 2 lemons
- 1/4 cup sugar
- 2 tablespoons water
- Crème fraîche, for serving
- Make the syrup Preheat the oven to 350°. Butter a 10-inch round cake pan, line the bottom with parchment paper and butter the paper. In a food processor, pulse the almonds with 2/3 cup of the pistachios until finely ground.
- In a large bowl, using a handheld electric mixer, beat the butter with the sugar at medium speed until it's the texture of moist sand. Add the eggs one at a time, beating well between additions. Add the lemon zest, lemon juice and vanilla seeds and beat until smooth. Gradually beat in the olive oil in a thin stream. Using a rubber spatula, fold in the ground nuts, flour and salt. Scrape the batter into the prepared pan.
- Bake the cake for about 55 minutes, or until a toothpick inserted in the center comes out clean. Transfer the pan to a rack and let the cake cool for 15 minutes. Invert the cake onto the rack and peel off the parchment paper. Invert the cake again onto a serving plate.
- Meanwhile, toast the remaining 1/2 cup of pistachios in a pie plate for about 8 minutes, or until fragrant.
- In a small saucepan, combine the lemon zest, lemon juice, sugar and water and bring to a simmer over moderate heat, stirring until the sugar is dissolved. Pour the syrup over the warm cake and scatter the toasted pistachios all over the top. Let stand for 1 hour, then cut into wedges and serve with crème fraîche.
The cake can be kept in an airtight container at room temperature for up to 2 days.