Peel the cucumber into ribbons, right down to the seeded core and all the way around. Put the ribbons in a bowl. Dice the core and add to the bowl.
Trim the carrots. Peel ribbons off them, just like you did with the cucumber. Add them to the cucumber ribbons. Dice the middle bits of the carrots and add them too.
Pick the thick stalks out of the watercress. Add the tender leaves and shoots to the bowl of
Pick the Thai holy basil leaves off the stalks. Finely slice the chilli, flicking out the seeds for less heat. Add most of the basil and chilli to the veg. Save some for garnish.
Juice the lime into a bowl. Add the vinegar and 1 tbsp olive oil. Season with salt and pepper. Whisk together to make a dressing. Taste and adjust the seasoning if you need to.
Warm 1 tbsp olive oil in a frying or griddle pan. Season the steaks on both sides with salt and pepper. Add to the pan. Fry for 1-3 mins on each side, depending on how well done you like your steaks.
Lift the steaks out of the pan. Wrap them loosely in foil. Leave them to rest for 5 mins.
Add the dressing to the salad. Toss to mix. Slice the steaks. Serve them with the salad, garnished with the basil leaves and chilli you saved in step 4.