Step 1

Preheat oven to 350 degrees F.

Step 2

Melt butter in a small saucepan; keep warm. Place thawed spinach in a colander; press to squeeze out as much water as possible. Roll the spinach in paper towels and press to get out any additional water. (The spinach should be quite dry.)

Step 3

Beat eggs in a large bowl. Add cottage cheese and feta; stir until well combined. Crumble the spinach into the egg mixture and add 3 tablespoons of the melted butter. Mix until well combined. Season with salt and pepper.

Step 4

Carefully unroll phyllo and lay the stack flat on a work surface. Cover with a dish towel, and then cover that dish towel with a second slightly dampened dish towel. (This keeps the phyllo from drying out while you work.)

Step 5

Brush the bottom of a 9-by-13-inch baking dish with a little bit of the melted butter. Lay a single sheet of phyllo in the pan. Lightly drizzle some butter onto the phyllo. Lay on another sheet, drizzling again with butter. Repeat until you have used half of the phyllo. Gently spread the spinach mixture on top of the phyllo. Layer the remaining phyllo sheets on top of the filling, drizzling each layer with butter. Drizzle the top layer with butter. (You should have used up most of the melted butter, but may have some left over.)

Step 6

Trim any overhanging dough to the edge of the pan with scissors. Using a paring knife, gently turn the edges of the dough under. With the knife, gently score the top of the spanakopita into 24 squares, cutting through the top few layers of dough. Use your fingers to sprinkle the top of the spanakopita with a bit of ice water (this makes the top extra crispy).

Step 7

Bake until the top layer is browned and crispy, about 1 hour and 15 minutes. Let cool slightly before cutting into squares. Serve warm or at room temperature.