Preheat your oven to 375°F (190°C). Line two baking sheets with parchment paper.
In a medium bowl, combine the chopped spinach, crumbled feta cheese, beaten egg, black pepper, and dried dill. Mix until the filling is evenly distributed.
Carefully unroll the thawed phyllo dough. Keep the sheets covered with a slightly damp kitchen towel while you work to prevent them from drying out.
Lay one sheet of phyllo dough flat on your work surface. Brush the entire surface lightly with melted butter.
Place a second sheet of phyllo dough directly on top of the first. Brush this second sheet lightly with melted butter.
Cut the stacked sheets into four equal squares.
Place about one tablespoon of the spinach and feta filling near one corner of a phyllo square.
Fold the corner over the filling diagonally to form a triangle. Press the edges firmly to seal. You can crimp the edges with a fork for extra security.
Place the finished crisp on the prepared baking sheet. Repeat this process with the remaining phyllo sheets and filling. You should have about 16 crisps.
Brush the tops of all the assembled crisps lightly with any remaining melted butter.
Bake for 12 to 15 minutes, or until the phyllo is golden brown and crisp.
Remove from the oven and let cool slightly before serving. These are excellent as quick feta finger food.
Notes
For an air fryer spinach feta snack, cook at 350°F (175°C) for 6 to 8 minutes, checking frequently to prevent burning.
Serve these baked Mediterranean bites with a side of tzatziki sauce for dipping.
If you prefer a richer flavor, mix 1 tablespoon of grated Parmesan cheese into the filling mixture.