Bring water to a boil. Add spinach, cover, and boil until spinach is defrosted. Place spinach in a colander and drain until barely moist. Set aside.
Heat oil in pan over medium-high heat. Add scallions and garlic and saute until scallions are soft. Add the spinach, feta, cottage cheese, dill, pepper, and salt. Stir to combine and remove from heat.
Place 1 phyllo sheet on a buttered sheet pan. (Cover remaining dough to keep from drying out.) Lightly coat sheet with melted butter. Coat 3 more phyllo sheets, one at a time, with melted butter and stack one on top of the other.
Spoon spinach mixture on top of the phyllo dough and spread evenly.
Brush remaining phyllo dough with butter and place on top of spinach mixture, making sure to press the phyllo down firmly. Score the top phyllo into a triangle shaped piece and butter the top of the phyllo.
Bake for 35 minutes or until golden brown. Cut into triangles. Serve warm.