The steak and onion sandwich is a genuine classic and one that is worth taking the time to make at home. The harmonious flavours of the Artichoke and Truffle Pesto bring a satisfying and luxurious addition to tried and tested flavour combinations and makes an excellent replacement for mayonnaise. Do try and use fresh horseradish as it really elevates the entire marriage of flavours.
Heat an oven to 200C fan / 210C non fan. Cut the onion in half and rub a little olive oil on the flesh side, followed by a little salt. Roast for 15 minutes then remove and allow to cool. Once cooled, remove the skin the cut each half into 2, separating the layers as the fall apart. Season with salt and pepper and set aside.
Season the steak generously with salt and pepper all over. Depending on how thick the steak is and how well you liked it cook, the cooking times can vary quite a bit. For instance, a long thin steak, like sirloin, will only need a few minutes on each side if you like it medium rare, whereas a thicker piece of rump would need longer. Remember, the steak will continue to cook whilst resting, and if it isn’t cooked enough, you can always cook it more.
Place a frying pan on medium to high heat and when hot, carefully lay the steak down. Cook on one side till the meat begins to brown and take on caramelisation, around 2 – 3 minutes, then turn over and cook for around the same time. It should be between rare to medium rare and if this is as you like it, take out on to a plate and allow to rest for at least 5 minutes.
Whilst the steak is resting, toast the ciabattas. Spread the cut half with some of the artichoke pesto. Thinly slice the steak, then layer up each piece of ciabatta with the meat and roasted onions. Add small blobs of the pesto on top, followed by any juices left by the steak. Finish by grating the fresh horseradish with a fine grater, followed by the leaves.