Step 1

Preheat the oven to 350°F (180°C). Line 2 large baking sheets with parchment paper. Grease a 9 x 13-inch (22 x 33 cm) baking dish with nonstick spray.

Step 2

Tear the phyllo sheets into uneven pieces, separating the layers, and evenly spread across the prepared baking sheets.

Step 3

Bake for about 20 minutes, until the phyllo is lightly toasted and hardened. Set aside to cool.

Step 4

Meanwhile, in a large bowl, use a whisk or electric hand mixer on medium-high speed to whip the sugar and the eggs together until doubled in volume, pale yellow, and thick, about 5 minutes.

Step 5

Add the sunflower oil, baking powder, vanilla, orange zest, and Greek yogurt. Beat for 1–2 minutes, until smooth.

Step 6

Crush the toasted phyllo into small pieces, then use a rubber spatula to fold into the egg mixture until well incorporated.

Step 7

Transfer the orange pie mixture to the prepared baking dish and spread in an even layer.

Step 8

Bake for about 40 minutes, until the top is golden and the filling is set. If the surface is browning too quickly, cover the pan with foil.

Step 9

While the pie is baking, make the orange syrup: In a medium saucepan, combine the orange juice, water, lemon juice, orange peel, and sugar. Bring to a low boil over medium low heat and cook until the sugar is dissolved and the syrup is slightly thickened, 10—12 minutes.

Step 10

Remove the orange pie from the oven and poke the surface all over with a fork.

Step 11

Slowly ladle the orange syrup over the cake, letting the pie soak up the syrup.

Step 12

Let the pie sit for about 1 hour to fully absorb the syrup, then slice and serve.

Step 13

Enjoy!