3Beat 5 large egg yolks, ½ cup (100 g) sugar, and reserved lemon zest in a large bowl with an electric mixer (either a hand mixer with beaters or a stand mixer with the paddle attachment) at high speed until thick and pale, about 3 minutes. Reduce speed to medium and add ¾ cup extra-virgin olive oil followed by reserved lemon juice, beating until just combined (mixture may appear separated). Using a rubber scraper, fold 1 cup (125 g) cake flour into wet ingredients until just combined.