Season the beef chuck cubes with 1/2 tsp each salt and pepper. Coat the pieces evenly so the seasoning stays with the meat through the braise.

Heat 1 tbsp oil in a large heavy-based pot over high heat, then brown one-third of the beef deeply on all sides and transfer it out. Work in batches with more oil as needed, listening for a steady sizzle rather than a watery boil.

Lower the heat to medium-high and cook the onion and garlic for 3 minutes in the same pot. The onion should soften and the garlic should smell fragrant without browning too quickly.

Stir the flour through the onion mixture until it coats the aromatics. This flour layer will give the finished gravy a velvety thickness.

Pour in the beef stock slowly while stirring, then add the wine, tomato paste, Worcestershire sauce, coarsely ground pepper, and bay leaves. Keep stirring until the flour dissolves and the liquid looks smooth rather than lumpy.

Return all browned beef and any collected juices to the pot, cover, and adjust the heat to maintain a gentle simmer. Small, lazy bubbles keep the meat moist while it slowly softens.

Cook covered for 1 hr 45 minutes, then uncover, raise the heat slightly, and cook for 30 - 45 minutes, stirring regularly. The beef is ready when a fork slides in easily and the gravy coats the back of a spoon while still coming just about up around the meat.

Remove the pot from the heat, cover the filling, and cool it completely before assembling the pies. Chilled filling should be thick and mound easily in the pastry shell without flowing toward the rim.

Heat the oven to 180C/350F. Allow the oven to come fully to temperature so the pastry begins setting as soon as it goes in.

Cut 6 rounds of shortcrust pastry and ease each round into a pie tin without pulling or stretching the dough. Let the pastry relax into the corners, since stretched dough shrinks back during baking.

Place the pie tins on a baking tray, line each shell with a generous piece of parchment paper, and fill with pie weights. The weights hold the sides upright and keep the bases flat.

Bake for 20 minutes, then lift out the parchment and pie weights using the paper overhang. Handle the hot weights carefully and keep the shells in their tins.

Return the empty shells to the oven for 5 minutes. The bases should feel dry and look light golden before they receive the filling.

Spoon the cooled beef filling into the baked shells and press it down gently, leaving it slightly mounded. Keep the filling below the rim so the lids can seal without gravy pushing out.

Cut puff pastry rounds slightly larger than the baked pastry bases while the puff pastry remains partially chilled. Cool pastry cuts cleanly and keeps its laminated layers intact.

Brush the edge of each shortcrust shell with egg, place a puff pastry round over the filling, and press the edges together firmly. A neat seal prevents the gravy from escaping as the pastry puffs.

Brush the tops with egg and cut a 1cm / 0.5" slit in the center of each lid using a small knife. The opening gives steam a path out while the tops turn glossy and golden.

Bake for 30 minutes. The pies are ready when the puff pastry is high, deeply golden, and bubbling gently at the center vent.

Serve the pies hot and fresh with tomato sauce or ketchup if desired. Let the bubbling settle briefly so the gravy stays inside the shell when cut.