Cut cold butter into one centimeter chunks. Place flour and butter in mixer, and use a paddle attachment on a mixer on low for a minute or two until you have coarse crumbs and pea-sized chunks of butter in your flour. Keeping the mixer on low, add cream cheese and continue mixing just until the dough comes together. Flatten into a rough rectangle, wrap and chill for at least an hour.
When ready to use, lightly flour a cutting board or your rolling surface. Roll dough out to a 1/2 centimeter thickness. Use a 10-12 centimeter round cutter to cut out circles. An offset spatula can help you lift them out if parts of the dough are a bit sticky. Brush your circle with the eggwash and place a tablespoon of the filling of your choice in the center. Pinch three evenly spaced points around the circle to make a triangle shape around your filling. When are your cookies are filled, chill them for another hour or freeze them for best results- baking the cold dough will help the cookies keep their shape.
When you’re ready to bake, preheat your oven to 350. Place the cookies on a parchment lined sheet, lightly brush the cookies with eggwash and sprinkle sesame seeds and a pinch of salt on top. Bake them for 10-15 minutes until golden and let them cool for five minutes before eating.
Boureka filling:
Thaw frozen spinach and squeeze out as much water as possible. Mix into a bowl with crumbled feta, ricotta, olive oil and garlic and egg until the mixture is even. Add the zest, salt and spices and mix until evenly distributed.