01 - Preheat the oven to 400°F. Line a baking sheet with parchment paper.
02 - Combine ground beef, onion, garlic, thyme, oregano, Worcestershire sauce, Dijon mustard, black pepper, salt, and parsley in a mixing bowl. Mix until fully incorporated.
03 - Roll out the puff pastry on a lightly floured surface. Cut the pastry sheet in half lengthwise to create two long rectangles.
04 - Divide the beef mixture in half. Shape each portion into a long sausage shape and place along the center of each pastry strip.
05 - Brush one long edge of each pastry strip with the beaten egg mixed with milk. Roll the pastry over the filling, sealing the edge. Place seam side down.
06 - Cut each long roll into 6 equal pieces, about 2 inches each. Place on the prepared baking sheet.
07 - Brush the tops with remaining egg wash. Sprinkle with sesame or poppy seeds if using.
08 - Bake for 20-25 minutes, or until golden and cooked through. Let cool slightly before serving.