Preheat your oven to 350°F (175°C) and grease a 9x13 inch baking dish.

Remove the phyllo dough from its packaging, unroll the sheets, and let them sit out on the counter to dry for about 20 minutes, then tear them into small, rough shreds.

While the phyllo dries, prepare the syrup by combining 1 cup sugar, 1 cup water, the juice of 1 orange, and a cinnamon stick in a saucepan.

Bring the syrup mixture to a boil, reduce heat, and simmer for 5 minutes until slightly thickened, then remove from heat and let it cool completely.

In a large mixing bowl, whisk together the eggs and the remaining 1 cup of sugar until the mixture is pale and frothy, about 2-3 minutes.

Add the Greek yogurt, vegetable oil, orange zest, vanilla extract, and baking powder to the egg mixture, whisking until everything is smooth and well combined.

Gradually add the shredded phyllo dough into the wet batter a handful at a time, folding gently to ensure the pieces are coated and not clumped together.

Pour the mixture into the prepared baking dish and bake for 40-45 minutes until the top is a deep golden brown and the center is set.

Remove the pie from the oven and immediately pour the cooled syrup evenly over the hot pie; the temperature difference is crucial for absorption.

Allow the pie to rest and soak up the syrup for at least 1 hour before slicing into squares to serve.