01 - Combine ground pork, onion, garlic, soy sauce, oyster sauce, sugar, black pepper, salt, cornstarch, and sesame oil in a mixing bowl. Mix thoroughly until all ingredients are well incorporated and the mixture becomes sticky.
02 - Preheat oven to 400°F. Line a baking tray with parchment paper and set aside.
03 - On a lightly floured surface, roll out puff pastry sheets to approximately 1/8 inch thickness. Cut into 10 circles using a 3.5-inch round cutter or pastry cutter.
04 - Place 2 tablespoons of meat filling in the center of 5 pastry circles. Brush the edges with beaten egg. Cover with a second pastry circle, pressing firmly to seal. Crimp edges with a fork to ensure proper closure.
05 - Brush the tops of assembled pastries with remaining beaten egg to achieve a golden, glossy finish during baking.
06 - Arrange pastries on the prepared baking tray, leaving 2 inches of space between each. Bake for 20-25 minutes until pastries are puffed and golden brown.
07 - Remove from oven and let cool on the tray for 5 minutes before serving warm.