I like to serve these sandwiches on a freshly baked Ciabatta bread so that the juices from the onions and the steak pools into the large porous holes of the bread. It makes the sandwich moist without being wet and serves to contain a lot of the juice that will flow out of the meat as you bite in to it.
The complete sandwich is three separate recipes. The steak (that’s this recipe),
the onions, and the bread. Only the first two are necessary to make for the meal if you already have suitable bread.
Units: Metric US Imperial
Take your steak out of the fridge and let it come to room temperature. You can hasten this along by putting the steak in a water tight Ziploc baggie and submerging in lukewarm water
Cook your awesome onions from the given recipe (takes about 45 minutes) in the notes
If you have freshly baked Ciabatta, use that, otherwise warm your bread up in a 110C/225F oven for ten minutes or so
Drizzle olive oil all over the steak
Season your steak with sea salt and black pepper. Give it a good rub in to the steak.
Put a large non-stick skillet or heavy pan over a high flame
Get that you skillet or pan scarily hot on the stove
Pop the steak in the pan and sear on each side for about 3 minutes or until it is done just the way you like it. One of those rare times (no pun intended) where I shoot for a medium rare steak.
Remove the cooked steak to a resting rack with a pan or plate underneath to let the juices leech out.
Cover the steak with a piece of tin foil and let it rest for a minute or two
Slice the steak in to 1cm thick pieces
Pour a small of olive oil in to the pan/plate with the resting juices and mix it up
Toss the cooked steak in the resting juices & olive oil mixture.
Cut your bread so that it will form one long, flat sandwich
Brush the resting juices from the steak over the bread
Apply mustard and lettuce as an optional step
Place slices of steak on the sandwich
Spread the onions over the steak
Finish the sandwich by topping with the other piece of bread