Preheat oven to 400 degrees F (200 degrees C). Lightly grease a baking sheet.
Beat eggs in a bowl using a fork or whisk; stir in feta cheese, garlic powder, and salt. Add spinach and bacon and mix well.
Unfold pastry sheets onto a lightly floured surface. Top each sheet with 1/2 of the spinach mixture and spread evenly. Starting with the short side, roll each like a jelly roll around the filling. Place rolls on a plate and freeze until firm, about 15 minutes.
Cut each roll into 20 slices using a sharp knife. Arrange slices onto the prepared baking sheet and top each with Parmesan cheese.
Bake in the preheated oven until pastries are golden brown, about 15 minutes. Transfer pastries to a wire rack to cool, about 10 minutes.