To make the filling, combine both the cheeses, egg, egg yolk and herbs in a bowl and mix well.
Cut the filo pastry into strips approximately 6cm (2 1/2 in) wide and 30cm (12in) long. Place in a pile and cover with a clean cloth to prevent them from drying out. Take one strip of filo pastry and brush lightly with oil. Place about 1 teaspoon of filling over the bottom end of the pastry strip. Carefully lift up the right-hand corner and fold over to make a triangle. Fold over and over again until you have reached the top. Repeat with the remaining filo strips and filling.
Place the filo pastry triangles side by side on a greased baking sheet and brush the tops lightly with oil. Sprinkle with nigella seeds and bake in a preheated 180ºC/350ºF/gas 4 oven for 15 minutes or until crisp and golden.
Excerpted with permission from Hazana: Jewish Vegetarian Cooking by Paola Gavin, published by Quadrille October 2017.