In a large bowl, place the cream cheese, cottage cheese, feta cheese, mozzarella cheese and eggs.
Mix until fully incorporated.
Make The Pastries
Preheat the oven to 375F (200C) and line one large baking sheet with parchment paper.
Gently roll your puff pastry into 1/8 inch thick.
Cut the sheet into 4 4x4 rectangles (or 5x5).
Line the squares over the prepared baking sheet and fold them into triangles.
Unfold them back into squares.
Top each square with 2-3 spoonfuls of cheese filling and brush the edges of the pastry with the egg wash.
Fold the empty side of the pastry over the cheese filling.
Use a fork to seal the edges of the pastries.
Brush with egg wash and sprinkle with sesame seeds or poppy seeds.
Bake for 15 minutes at 375F (200C), then reduce the temperature to 350F (180C) and bake for another 20-25 minutes.The pastries are ready when the top and bottom are deep brown. If the tops brown faster, cover them with aluminum foil. Pay attention to the color of the pastires, if they are not baked all the way, they will deflate as they cool, and the pastry dough layers inside will remian raw.