Heat oven to 375°F. In small bowl, mix feta cheese, green onions and 3 tablespoons of the beaten egg.
If using crescent rolls: Unroll dough; separate into 4 rectangles. Press perforations to seal. If using dough sheet: Unroll dough; cut into 4 rectangles.
Press each rectangle into 7 1/2x5-inch rectangle. Cut rectangle into 3 rows by 2 rows to make 6 (2 1/2-inch) squares. Top each dough square with slightly rounded measuring teaspoon feta cheese mixture. Fold dough over filling, forming triangle; press edges to seal. On ungreased cookie sheets, place triangles 2 inches apart. Repeat with remaining 3 dough rectangles and feta cheese mixture.
Brush tops with remaining beaten egg. Sprinkle lightly with Parmesan cheese.
Bake 9 to 11 minutes or until golden brown. Serve warm.