Prepare springform: Preheat the oven to 400°F/ 200°C. Brush the springform with oil, both the bottom and the sides. Line the bottom with a circle of parchment paper. Place some oil in a small bowl for brushing the dough.2-3 tablespoons olive oil Roll the dough layers: Place one dough ball on a lightly floured surface. Roll it into a large circle, then gently stretch it further with your hands, as you would for strudel dough, until very thin. It should be large enough to cover the pan and extend over the edges, and thin enough that you can almost see your hand through it.
Line the springform with dough: Place the first sheet of dough into the prepared springform, letting it cover the sides and hang slightly over the edge. If it doesn’t fully cover the pan, don’t worry - just cover as much as possible and adjust with the next layer.
Brush the dough lightly with oil.
Repeat with another 2 pieces of dough (or 3 if you decided to make 4 layers), brushing each layer with oil, but leave the last one unbrushed.
Fill the pie: Add the spinach filling to the pan and smooth the surface. Make four small indentations with a spoon. Place a tiny piece of butter into each indentation.
Add eggs: Carefully crack one egg into each indentation. Season with salt and pepper and sprinkle with the remaining Parmesan.4 large eggs + fine sea salt and ground black pepper Cover the pie: Roll and stretch the remaining dough pieces one by one. Place them over the filling and brush each layer with oil, including the last one.
Finish the edges: Break the remaining butter into very small pieces and place them close together all around the edge of the pie. Fold the overhanging dough edges inward over the butter, rolling and pressing them lightly to seal the edge. Brush the top lightly with oil.1 oz butter Prick the top gently with a toothpick in several places, without going too deep, so you don’t pierce the eggs.
Bake the spinach pie for about 75 minutes until the filling is set and feels firm to the touch. If the top is getting too dark, cover loosely with foil – check after about 45 minutes.
Serve Italian pie: Let it rest for at least 15 minutes before slicing it. Serve it warm or at room temperature.