Preheat your oven to 375°F (190°C) and lightly grease a small oven-safe baking dish with a drop of olive oil.
Sauté the fresh spinach and minced garlic in a large skillet over medium heat until the spinach is completely wilted.
Transfer the cooked spinach to a clean kitchen towel or fine-mesh strainer and squeeze out as much liquid as possible to ensure a crisp crust.
In a medium mixing bowl, whisk together the egg, liquid egg whites, Greek yogurt, sea salt, black pepper, and ground nutmeg until smooth.
Stir in the crumbled feta cheese, chopped fresh dill, and the squeezed-dry spinach until the mixture is well combined.
Lay one sheet of phyllo dough into the prepared baking dish, letting the edges hang over the sides, and brush very lightly with a small amount of olive oil.
Repeat the layering process with the remaining two sheets of phyllo dough, brushing lightly with oil between each layer.
Pour the spinach and egg filling into the center of the phyllo sheets, spreading it out evenly.
Fold the overhanging edges of the phyllo dough over the top of the filling to create a rustic border.
Brush the top of the folded dough with the remaining olive oil to help it brown.
Bake for 30 to 35 minutes until the phyllo is deeply golden brown and the egg filling has completely set in the center.
Allow the pie to cool for 5 minutes before slicing and serving.