Preheat oven to 400°F (200°C). Line a baking sheet with parchment paper.

Heat olive oil in a large skillet over medium heat.

Add diced onion to the skillet and cook until translucent.

Add thawed spinach to the skillet and cook until heated through, removing excess moisture.

Remove skillet from heat and let the spinach mixture cool slightly.

In a bowl, combine the spinach mixture, minced garlic, cottage cheese, crumbled feta cheese, Greek seasoning, nutmeg, and salt.

Melt butter in a small bowl.

Lay two phyllo sheets vertically on the prepared baking sheet and brush with melted butter.

Continue layering phyllo sheets in a clockwise fashion, brushing each set of two sheets with melted butter.

Once all phyllo sheets are used, spread the spinach mixture evenly in the center, forming a circle.

Carefully fold the phyllo dough over the edges of the spinach mixture, leaving the center filling visible.

Brush the edges with melted butter.

Bake for 25-30 minutes, or until the edges are golden brown and the center is set.