Trim most of the white stalks from the silverbeet and discard. Roughly chop the remaining stalks and leaves and rinse (do not dry).
Heat a large pan over a medium low heat and add the silverbeet. Cook for 10 minutes or until most of the liquid has evaporated and the stalks are soft (you may need to do this in batches). Remove from the pan and set aside.
Heat the same pan again, add the olive oil and onion and cook for 2–3 minutes until tender. Add the garlic and continue cooking for a minute.
Meanwhile, combine the ricotta, three lightly beaten eggs, lemon rind, parmesan, nutmeg, salt and pepper in a large bowl. Add the onion once it has softened.
When the silverbeet is cool enough to handle, squeeze as much moisture out as you can, finely chop then add the ricotta to the mixture. Set aside.
Brush a 26cm springform cake tin with oil. Line the base with a sheet of filo, laying it a little off centre so the excess falls over the side of the tin. Brush with more oil and top with another sheet, laying it at an angle to the first sheet and allowing the excess to fall over the side of the tin. Continue brushing with oil and layering with filo.
Once finished, spoon in the ricotta mixture. Make five indentations in the filling with the back of a wooden spoon and crack an egg into one.
Fold the overhanging filo back into the centre of the tin to fully enclose the filling. Brush with a little more oil.
Bake for 50–55 minutes until golden brown and firm. Note that if your pie starts to brown to quickly, cover with foil. Stand for 5–10 minutes before gently removing from the tin. Serve with a simple salad.