Add the spinach, olive oil, salt and pepper to a large bowl, and toss to combine. Massage the spinach by squeezing it with your hands until it’s wilted, greatly reduced in volume and it’s released some of its juices.
Crumble in the feta cheese and toss well until it’s evenly distributed throughout the filling. At this point, you can taste the filling and adjust the seasoning as needed.
Cover tightly and place in the fridge until needed.
Making the filo dough:
You can make the filo dough either by hand or with a stand mixer fitted with the dough hook attachment.
In a large bowl, or the bowl of a stand mixer (if using), mix together the psyllium husk and water. After about 30-45 seconds, a gel will form.
In a separate bowl, whisk together the gluten free flour blend, sugar, xanthan gum and salt until well combined.
Add the melted butter to the psyllium gel and mix well to combine, then add the dry ingredients. Knead, either by hand or with a stand mixer, until you get a smooth, supple dough that comes away from the sides of the bowl. The dough might be slightly tacky to the touch, but it shouldn't be too sticky.
Divide the dough into 6 equal pieces, each should weigh about 68g. Working on a lightly floured surface, shape them into smooth balls.
As you’ll be working with one portion of dough at a time, keep the others covered with a sheet of plastic wrap/cling film or a damp tea towel to prevent them from drying out.
Rolling out the filo pastry:
When you’re rolling out the gluten free filo pastry, it’s important that you work on a generously floured surface to prevent it from sticking. You can use the gluten free flour blend for flouring, but I’ve also used millet flour with great results.
Roll out one portion of the filo pastry into a large rectangle, about 10x13 inches (25x33cm) in size – but if you can get it larger (and therefore thinner), that’s even better. It may initially seem impossible to get it that large, but trust the process. And when you think you can’t possibly go any thinner, continue rolling it out anyway. In the end, the filo pastry should be so paper-thin you can actually read through it.
Don’t worry if the edges of your rectangle aren’t perfectly neat and if it's slightly irregular in shape – it won't matter once you start assembling the parcels.
Note about the rolling technique: Instead of pressing down too much on the rolling pin, it’s better to just slide it along the surface of the pastry so that it gently rolls over it. In effect, you’re not really rolling out the pastry by pressing down on it, but rather using the rolling pin to slowly stretch it out.
Always roll the rolling pin from the centre towards yourself. If you want to roll or “stretch” the pastry in a particular direction, don’t try to rotate the pastry. Instead, move around the work surface and again roll the rolling pin from the middle towards yourself. Repeat this process until you’ve rolled the pastry from all four perpendicular directions into a large rectangle.
Assembling the spanakopita parcels:
I recommend having a look at the blog post for detailed step-by-step photos of the assembly process.
Once you’ve rolled out the pastry into a large rectangle, use a sharp knife, a pizza cutter or a bench scraper to create four slits, two along each of the longer sides of the rectangle, so that you essentially divide the dough into three sections. This will make the folding process easier. (Note that you’re not actually cutting the rectangle into three separate sections, each slit should reach only about one third of the way towards the centre of the rectangle.)
Brush the pastry rectangle all over with melted butter.
Place a generous amount of the spinach feta filling in the centre of the bottom third of the pastry. Fold the “flaps” of the bottom third over the filling.
Place another portion of the filling in the centre of the middle third of the pastry, and fold the bottom third (the part you’ve just filled) over it.
Fold the “flaps” over the central part, then fold it over the top third, and fold the remaining “flaps” over the parcel.
Transfer the assembled parcel onto a large baking sheet lined with parchment/baking paper. Make sure to place it with the flaps facing down, to prevent them from opening up during baking.
Repeat the rolling out and assembling process with the rest of the filo pastry and filling. While you're assembling the pastries, start preheating the oven.
Baking:
Adjust the oven rack to the middle position and preheat the oven to 400ºF (200ºC).
Brush the tops of the parcels with more melted butter, and bake them at 400ºF (200ºC) for about 40-45 minutes or until they’re deep golden brown in colour and the pastry is perfectly crisp.
Transfer them to a wire rack to cool slightly, then serve them hot, warm, or cooled completely to room temperature.
Storage & reheating:
The gluten free spanakopita parcels are amazing both hot and cooled completely to room temperature. You can store them in a closed, air-tight container in the fridge for up to two days and reheat them before serving.
To reheat them, arrange them on a baking sheet and place them into a 350ºF (180ºC) oven for about 15 minutes, until they’re thoroughly heated through and the pastry is crisp. I don’t recommend reheating them in the microwave, as that won’t crisp up the pastry.