Combine the warm water, sugar and yeast in a bowl. Add the flour and salt and mix together until well combined. Transfer the dough to a floured surface and knead the mixture until sticky, about 5 minutes.
Add the olive oil and continue kneading until the dough becomes soft and smooth and lightly sticky without leaving any dough on your fingers. The dough will be oily.
Transfer the dough to a lightly greased and allow it to proof until doubled, about 90 minutes.
Remove the dough and divide into 30 pieces and reshape into round balls. Let sit in an oiled tray covered until doubled, about 30 minutes.
Make the stuffing
In a large bowl, place the thawed spinach, parsley, onions, olive oil, lemon juice, sumac and and salt. Stir to combine until very well mixed. Set aside in the fridge until ready to use.
Assemble & Bake
Preheat the oven to 425ºF and line two baking sheets with parchment paper.
Divide the dough into the two trays with 15 balls each separated into 3 rows of 5. Use your hands to press down on the dough to flatten them while keeping a circular shape.
Place 2 tablespoons of the mixture inside each circle.
Hold two ends of the dough and seal them together over the filling, pinching the dough together to help bind. Fold the last side up to meet the first two sides, pinching the dough together with the first two sides to bind.
Bake for 15-20 minutes until the tops are golden brown.
Serve warm on their own or with plain whole milk yogurt as a dip.
Video
Notes
Storage: Store any leftovers in an airtight container. They will last about 5-7 days in the fridge. Reheat in the microwave or oven until warmed through or enjoy cold.Make Ahead Tips: You can prepare the stuffing up to 5 days in advance because the mixture benefits from softening as is sets.Freezing Instructions: You can freeze the spinach pies before cooking by placing them on a baking sheet in the freezer. When frozen, transfer to an airtight container or freezer bag and keep for 3 months. You can also freeze the baked spinach pies after they've cooled completely.Substitutes: For best results, follow the recipe as is. However here are some common substitutes that would work well in this recipe.
Instead of frozen spinach, you can use 16 ounces fresh spinach. Add it to a skillet with a teaspoon of olive oil and allow the spinach to wilt completely and cook off any moisture released before removing from the heat. Cool completely and add the remaining ingredients
Instead of parsley, you can use more cilantro, but parsley is more traditional.
Instead of lemon juice, you can use 2 teaspoons citric acid
Instead of sumac, you can substitute lemon pepper seasoning.