5. Roll up the pastry wth the beef inside, pressing where the pastry meets to seal it, then transfer to a lined baking tray, with the seal at the bottom. Pinch and twist the ends of the pastry to form a cracker shape, then brush all over with egg. Trim 1-2cm from the ends and reroll the offcuts; use a cutter to cut out the snowflake shapes and stick them onto the Wellington.