
Thaw the puff pastry at room temperature for 40 minutes.
Set oven to 400 degrees F.
Lightly grease a baking sheet.
In a small cup or bowl whisk together 1 egg with water; set aside.
In another bowl mix together 2 eggs, feta cheese, spinach, onion, parsley and black pepper.
Unfold the pastry sheets on a lightly floured surface.
Roll each sheet into a 12-inch square.
Cut each into 16 (3-inch) squares (I use a pizza cutter for this!).
Place about 1 tablespoon spinach/cheese mixture in the middle of each square.
Brush the edges with egg mixture.
Fold squares over the filling to form triangles.
Crimp edges to seal.
Place on a baking sheet, and brush tops with remaining egg mixture.
Bake for about 20 minutes or until golden.
Best served warm or at room temperature.