Leek Pie (Prasopita)

To make pastry: Sift flour, salt and baking powder into a large bowl. Stir in enough water to make a dough that is soft but not wet. Stir in 1 tablespoon of the oil. Turn out onto a floured work surface and knead until smooth and elastic, 8 to 10 minutes, adding flour as needed. (Alternatively, combine flour, salt and baking powder in a food processor. With the motor running, slowly add water until the dough forms a ball. Add 1 tablespoon of the oil and process for 30 seconds. Turn out onto a floured work surface and knead briefly.) Cover with plastic wrap and let rest for 1 to 2 hours in the refrigerator.

To make filling and assemble pie: Heat oil in a large heavy skillet over medium heat. Add as much of the sliced leeks as will fit in the pan, adding the remainder as the first batch cooks down. Cook, stirring occasionally, until tender, 12 to 15 minutes. (Reduce heat to low if the leeks begin to brown, and add a little water if they begin to stick.) Transfer to a medium bowl and let cool. Toss with parsley, dill, mint, lemon juice and zest. Season with salt and pepper and set aside.

Preheat oven to 350 degrees F. Lightly oil a shallow 2-quart baking dish or coat with nonstick cooking spray.

Whisk together egg white, the remaining 2 tablespoons oil and a pinch of salt in a small bowl. Divide dough into 2 portions, one portion slightly larger than the other. Cut each portion in half. On a floured surface, roll out one of the larger pieces into a circle about 1 inch larger than the baking dish. Pick up the dough and ease it into the dish. Stretch dough so that it extends to the lip of the dish. Brush with the egg-white mixture. Repeat with the second larger piece, laying it over the first and brushing with the egg-white mixture.

Sprinkle rice or bulgur over the dough in the dish; this will soak up juices as the pie cooks. Spoon in the leek mixture. Roll out one of the remaining pieces of dough into a circle the same size as the dish. Place it over the filling and brush with the egg-white mixture. Repeat with the remaining dough, brushing the top with the egg-white mixture. Pinch top and bottom crusts together to seal. With a fork or the tip of a sharp knife, prick the top decoratively. Sprinkle with sesame seeds. Bake until golden, about 1 hour. Serve hot or at room temperature.