Kurdish-Style Rolled Pastry with Hazelnuts

The Turkish name for this pastry— kürt böreği —suggests it is a Kurdish speciality, but you should not expect to find it in eastern Anatolia, where the Kurds live. The name seems to have arisen because it’s the kind of dish Istanbul chefs imagine Kurds might eat. To confuse the issue further, I’ve boosted it with hazelnuts and crème pâtissière, which makes it more like the kind of rich pastry they love on the Black Sea.