Pistachio-Topped Lemon-Olive Oil Cake

• MAKE-AHEAD
• VEGETARIAN

Cake

1. 3/4 cup whole blanched almonds
2. 2/3 cup plus 1/2 cup unsalted pistachios (about 7 ounces)
3. 6 tablespoons unsalted butter, softened
4. 1 1/4 cups sugar
5. 4 large eggs
6. 1 tablespoon finely grated lemon zest
7. 1 tablespoon fresh lemon juice
8. 1 vanilla bean, halved lengthwise and seeds scraped
9. 1/4 cup plus 2 tablespoons extra-virgin olive oil
10. 2/3 cup all-purpose flour
11. 1/4 teaspoon salt

Syrup

1. Finely grated zest of 1 lemon
2. Juice of 2 lemons
3. 1/4 cup sugar
4. 2 tablespoons water
5. Crème fraîche, for serving

1. 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.
2. 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.
3. 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.
4. Meanwhile, toast the remaining 1/2 cup of pistachios in a pie plate for about 8 minutes, or until fragrant.
5. 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.