Philly-Style Cheesesteak Sandwich With Mustard Potato Salad

Preheat the oven to 220°C/ 200°C (fan)/ gas 7 and boil a kettle

Take your steak out of the fridge, open the packet and let it adjust to room temperature, chop your waxy potatoes in half, then add to a pot of plenty of boiled water with a pinch of salt and bring to the boil over a high heat

Once boiling, cook for 12-15 min or until fork-tender, then drain and rinse them under cold water until cooled slightly (save the pot for later!)

Whilst the potatoes are cooking, heat a large, wide-based pan (preferably non-stick with a matching lid) with a drizzle of vegetable oil over a high heat

Pat your rump steak[s] dry with kitchen paper and season both sides with a pinch of salt, once very hot, add the seasoned steak to the pan

For rare, cook for 2 min max on each side; for medium-rare, cook for 2-3 min on each side; for medium, cook for 3-4 min on each side, once the steak is cooked, transfer to a plate to rest and reserve the pan

Meanwhile, peel and finely slice your brown onion[s]

Deseed your pepper[s] (scrape the seeds and pith out with a teaspoon) and cut into thin strips

Return the pan to a medium heat, add the sliced onion and pepper strips with a pinch of salt and cook, covered, for 6-8 min or until starting to caramelise

While the onion and pepper are cooking, trim, then slice your spring onion[s]

Grate your cheddar cheese

On a clean chopping board, slice the rested steak as finely as you can

Combine your mayo and wholegrain mustard in the reserved pot with a pinch of salt and pepper and give everything a good mix up

Add the cooled potatoes and crush them lightly with a fork

Add most of the sliced spring onion (save some for garnish!) and give everything a good mix up – this is your potato salad

Once the onion and pepper has caramelised, add the sliced steak and your soy sauce to the pan and give everything a good mix up

Top with the grated cheese and cook, covered, for 2-3 min further or until the cheese has melted – this is your Philly-style cheesesteak filling

Add your baguette[s] to a baking tray (or two!) and put the tray[s] in the oven for 2-3 min or until warmed through and crusty

Slice the warmed baguette in half (without cutting all the way through), then open it out like a book and load in the steak filling