Sift the flour into a bowl, add the salt, vanillin, sugar, half the egg and the dry yeast dissolved in the warm milk.

Knead the dough with a dough hook or by hand; work in the vegetable oil at the end. Shape into a ball, cover with plastic wrap and leave in a warm place for 1.5 hours.

The pie is sized for an 18 cm (7-inch) pan - weigh out 250 g of the risen dough. For the filling, flake the tuna and mix it with the grated cheese, herbs and seasoning to taste.

Divide the dough into two pieces, one larger and one smaller. Press the larger piece into the pan, forming sides about 2 cm high, and spread the filling over it.

Roll the smaller piece out thinly, lay it over the pie and pinch the edges together all around the rim. If you like, slash the top layer with a knife.

Let the pie proof for 30 minutes, brush with the remaining half egg and bake for 25-30 minutes at 180 °C (350 °F). Enjoy!