This is a wheat-free cake, very light and fluffy, soaked in a zesty syrup. Cakes are not as popular as filo pastries in the Eastern Mediterranean, but this is a specialty of the Jewish quarter on the Asian side of Istanbul.
Preheat the oven to 350°F.
Make the syrup:
In a saucepan, bring 2/3 cup water to a boil. Add the sugar and orange juice and simmer for 10 to 12 minutes, until the sugar has dissolved and the mixture is thick and syrupy. Remove from the heat and let cool. Stir in the orange flower water and orange zest.
Make the cake:
In a bowl, with an electric mixer on high speed, beat the egg yolks with the sugar until thick and pale. Fold the hazelnut flour into the yolk mixture. In a separate bowl, whisk the egg whites until stiff and glossy, then gently fold them into the hazelnut mixture.
Grease the loaf pan and line with parchment paper. Pour in the batter. Bake for about 30 minutes, until lightly golden. Remove the cake from the oven and evenly pour the cooled orange syrup over the top.
Combine the yogurt, confectioners' sugar and passion fruit pulp in a bowl. Serve generously with the warm cake.
Photo: Jonathan Lovekin