Take the thawed spinach and squeeze out as much excess water as possible. Add to a large mixing bowl with the ground almonds. Roughly chop the walnuts and cranberries, crush the garlic and finely dice the onion. Add all to the bowl with the spinach. Crumble in the feta cheese and mix well to combine.
Preheat the oven to 400 degrees Fahrenheit. Crack the eggs into a bowl, season with salt and pepper. Add the thyme, Parmesan, and nutmeg. Beat well to combine. You may add more spices, herbs and seasoning as desired.
Spoon the spinach mixture into the base of a medium-sized oven dish. Make sure the mixture is an even layer. Pour the beaten egg mixture over the top, coating the spinach and vegetables.
Transfer to the oven for 20-25 minutes or until golden brown on top. The pie should be piping hot through and bubbling. Allow to cool a little before slicing and serving.