In a pan over medium heat, melt butter, and add onion and fresh parsley (or fresh coriander). Cook until translucent and soft for 3 minutes.
Add cooked shredded chicken, soy sauce, coriander powder, black pepper, red chili flakes, garlic, and ginger. Cook for 2 minutes; add flour to the mixture and mix quickly.
Add chicken stock and cook for 1-2 minutes until it thickens.
Cool the mixture until it is at room temperature.
Preheat the oven to 400 degrees F and line two baking sheets with parchment paper.
Place the puff pastry sheet on a flat surface. Cut each sheet into squares or circles.
Brush the puff pastry square with the egg wash, and add 2 tbsp of the chicken mixture. Place another square on top and seal the edges with a fork.
Place them on the baking sheet. Repeat for the rest of the puff pastry squares. Brush the top with the egg wash and sprinkle with sesame seeds
Bake for 20 minutes. Broil on high until lightly golden on top.