01 - Preheat oven to 350°F. Lightly grease a 9x13 inch baking dish with oil or butter.
02 - Remove phyllo from packaging and let sheets dry uncovered for 1 hour. Crumple dried sheets into rough, irregular pieces.
03 - Whisk eggs and sugar in a large bowl until pale and thick, about 3 minutes. Add yogurt, oil, vanilla, orange zest, and baking powder. Mix until fully combined.
04 - Gradually fold crumpled phyllo pieces into the batter, ensuring all pieces are evenly coated.
05 - Spread mixture into the prepared baking dish and smooth the surface. Bake 40-45 minutes until golden brown and a toothpick inserted in the center comes out clean.
06 - While pie bakes, combine water, sugar, orange juice, cinnamon stick, and orange zest in a saucepan. Bring to a boil, then reduce heat and simmer 8 minutes until slightly thickened. Remove cinnamon and zest. Allow syrup to cool completely.
07 - Remove baked pie from oven. Slowly pour cooled syrup evenly over the hot pie. Allow to cool completely and let soak at least 2 hours before serving.