This is a kind of Asian steak au poivre sandwich using fragrant szechuan peppercorns instead of normal ones. I'm using beef skirt or hanger steak (onglet) here, as it has much more flavour than any other cut of beef. I've made a wasabi mayonnaise here, or you could use freshly grated horseradish instead.
4 pieces of beef flank (bavette) or hanger (onglet), weighing about 140-150g each
Vegetable or corn oil for brushing
1tbsp of szechuan peppercorns, lightly crushed with the bottom of a saucepan
2-3tbsp good-quality mayonnaise
Wasabi, to taste
16 or so spring onions
1 large baguette
Bash the steaks a little with a steak hammer, then season them with sea salt and the crushed peppercorns. Heat a ribbed griddle pan or heavy frying pan until almost smoking and rub with a little oil. Cook the steaks for about 3-5 minutes on each side, depending on the thickness, keeping them nice and rare. Leave to rest for 3-4 minutes.
Meanwhile, mix the mayonnaise with enough wasabi to taste. Cook the spring onions on the griddle for a couple of minutes, turning them a few times. To serve, cut the baguette into equal pieces and cut in half lengthways.
Spread the bread with the mayonnaise, slice the steak as thinly as possible and arrange on the bread with the onions on top.