Mix the flour, suet and salt with enough cold water to form a soft but not sticky dough. Knead for a minute until smooth, wrap and set aside while you make the filling.
Brown the mince in a dry pan over a medium-high heat, breaking it up, until no pink remains. Add the onion and cook for 5 minutes until softened. Crumble in the stock cube, add the Worcestershire sauce and season with pepper. Take off the heat and cool for 10 minutes.
Divide the pastry into 4 and roll each piece into an oval about 20 cm across. Pile a quarter of the filling on one half, leaving a 2 cm border. Wet the border, fold the pastry over and press the edges together firmly, then crimp with a fork.
Wrap each pudding in a double layer of greased foil, twisting the ends like a boiled sweet wrapper. The foil replaces the traditional cloth, hence the name.
Steam over a pan of simmering water for 2 to 2 and a half hours, keeping the water topped up so the pan never boils dry.
Unwrap carefully, there is steam trapped inside. Serve with mash, peas and a jug of gravy.