Preheat your oven to 375°F.
While it's heating, cook the onion and garlic in a pan until softened.
This should take about 5 minutes.
In a bowl, mix the sautéed onion and garlic with ground pork, breadcrumbs, parsley, salt, and black pepper until well combined.
Roll out the puff pastry sheets on a lightly floured surface.
Cut each sheet in half lengthwise, giving you four strips of pastry.
Place a log of the pork mixture along one edge of each strip.
Brush the opposite edge with beaten egg, then roll the pastry to encase the filling.
Seal the edges tightly.
Cut each roll into pieces about 2 inches long, place them seam-side down on a baking sheet, brush with milk, and sprinkle with sesame seeds.
Bake for 25-30 minutes or until golden brown.