01 - Preheat oven to 400°F and line a baking sheet with parchment paper.
02 - Combine ground beef, onion, garlic, parsley, thyme, Worcestershire sauce, salt, pepper, and 1 beaten egg in a large bowl. Mix until thoroughly incorporated.
03 - Place thawed puff pastry sheets on a lightly floured surface. Cut each sheet in half lengthwise to create 4 long strips.
04 - Divide beef mixture into 4 equal portions. Form each portion into a long log and position down the center of each pastry strip.
05 - Fold pastry over filling and press edges firmly to seal. Place rolls seam-side down and cut each into 3 equal pieces, yielding 12 rolls total.
06 - Arrange rolls on prepared baking sheet. Whisk remaining egg with milk and brush over tops for golden browning.
07 - Use a sharp knife to cut small diagonal slits on top of each roll to allow steam escape during baking.
08 - Bake for 20-25 minutes until pastry achieves deep golden brown color and filling is completely cooked through.
09 - Allow rolls to cool for 5 minutes before serving to set filling and prevent burning.