In a large bowl, sift together flour, baking powder, and salt. Make a well in dry ingredients, and add butter, 1 cup (226 grams) cream cheese, 1 whole egg, and 1 egg white. Mix ingredients with your hands to make a soft dough. Dough should not stick to hands. Sprinkle with additional flour if too sticky. Cover bowl with plastic wrap, and let stand for 20 minutes.

Preheat oven to 350°. Grease 2 baking sheets.

In a medium bowl, stir together feta, parsley, and remaining ¼ cup (55 grams) cream cheese.

Shape dough into 16 (40-ounce) balls. Press each ball into a circle about 3 inches in diameter. Put a small amount of cheese filling on one half of each circle, and fold other half over to cover.

Place on prepared pans. Brush tops with egg yolk. Sprinkle with sesame seeds. Bake until tops are golden brown, about 30 minutes.