Add the potatoes to a bowl and drizzle with some olive oil and season with salt and pepper. Put in a preheated oven at 200c for 35 minutes. 10 minutes before the potatoes are cooked, pour the balsamic vinegar over the potatoes, stir and put back in the oven for the reminding 10 minutes.
Make the dressing by mixing together the olive oil, lemon juice, soy sauce, coriander, parsley, garlic, red chilli flakes, paprika, cumin and salt and pepper.
Add a little oil to a pan, season the steak and then cook on 2 minutes each side for medium. Set aside and cut in to strips.
In a large dish, add the lettuce, cucumber and tomato, cooked potatoes and sliced steak.
Drizzle the chermoula on top and then crumble over goats cheese. To finish, sprinkle with crumbled goat cheese, red chillies and spring onion.