For the dough:
- 2 1/2 cups all-purpose flour
- 3/4 teaspoon salt
- 1 egg
- 3 tablespoons olive oil
- 1/2 cup seltzer
- Melted butter
- 4 ounces Armenian string cheese or mozzarella
In the bowl of a standing mixer fitted with a paddle, mix the flour and the salt. Add the egg, oil, and seltzer, and mix to form a soft dough. Turn out the dough and knead, by hand, for 1 minute, until the dough is elastic.
Divide the dough into 4 pieces, form into balls, cover in plastic, and let rest in the refrigerator for 1 hour.
Preheat oven to 350 degrees F.
When chilled, roll the ball into a square. Trim the edges, and brush with melted butter. Fold the dough in half, and brush with butter. Fold the dough in half again, to make a square. Place 1/2 cup Spinach-Cheese Filling in the center. Sprinkle with some string cheese. Fold up the corners like a half open envelope. Repeat with remaining ingredients. Bake for 25 minutes.