Lightly grease 11 x 7 inch tin with olive oil and preheat fan-forced oven to 410° F.
Cut out stems of silverbeet then wash leaves and dry thoroughly*. Shred leaves and tip into large bowl.
Take one sheet of filo pastry, brush with olive oil and lay another on top; repeating the process until four sheets are stacked on top of one another. Place layered pastry in pie tin, gently pushing into the corners of the tray.
Tip silverbeet mixture onto pastry and even it out using your fingertips. Fold the edges of pastry onto the filling, then brush edges of pastry with olive oil and lay another filo sheet on top to seal. Add the last sheet of filo and brush liberally with olive oil.
Using the tip of a small knife, divide the pie into quarters taking care not to cut all the way through. With scissors cut two steam holes into each section.
Bake in oven for 30-35 minutes or until golden brown. Slide out of tin onto cooling rack and leave for 15 minutes before cutting into sections.
Don’t skip the note to fold the overhanging filo pastry back on top of the silverbeet mixture - I somehow overlooked that and it made a strange crispy crust (as you can see in the photo). The filling recipe is straight forward but it’s important you dry the silverbeet thoroughly (I used tea towels) after washing it; any moisture will make the pastry soggy. And on that note, while spanakopita’s translation is spinach pie Julie tells me silverbeet is used over spinach because it gives off less moisture.