Preheat your oven to 375°F (190°C).
Thaw the frozen spinach completely and squeeze out all excess moisture using a clean kitchen towel until the spinach is very dry.
In a large mixing bowl, whisk together the eggs, liquid egg whites, and non-fat Greek yogurt until the mixture is smooth and well combined.
Fold in the dried spinach, crumbled feta cheese, chopped scallions, fresh dill, sea salt, black pepper, and ground nutmeg.
Lightly brush a small oven-safe baking dish with one teaspoon of the olive oil.
Lay one sheet of phyllo dough into the dish, allowing the edges to hang over the sides, and lightly brush with a portion of the remaining olive oil.
Place the second sheet of phyllo on top at a different angle to cover more surface area and brush again with oil.
Pour the spinach and egg mixture into the center of the phyllo dough.
Gently fold the overhanging edges of the phyllo dough back over the filling, leaving the center slightly exposed for a rustic look.
Bake for 30 to 35 minutes until the egg filling is fully set and the phyllo crust is deep golden brown and crispy.