Pakistani Bakery Style Chicken Patties

Name: Pakistani Bakery Style Chicken Patties
Prep time: 30 min
Cook time: 20 min
Total time: 50 min
Cuisine: Asian
Ingredients: 2 tablespoons butter; ½ cup onion (finely chopped); ¼ cup parsley (finely chopped, You can also use fresh coriander ); 150 grams boneless chicken (boiled & shredded, I used shredded rotisserie chicken); 1 tablespoon soy sauce; ½ teaspoon black pepper; ½ teaspoon coriander powder; ¼ teaspoon red chili flakes; 3 cloves garlic; 1 teaspoon fresh ginger; 2 tablespoons all-purpose flour; 1 cup chicken stock (or whole milk); 2 puff pastry sheets; 1 egg (for egg wash); sesame seeds black and white (optional)