For the dressing
Whisk together all the dressing ingredients in a small bowl, until the sugar has dissolved.
Place the onions, cucumber, radishes and tomatoes in a bowl and pour over half the dressing. Leave to marinate whilst you cook the beef.
Brush the steak with the oil and season with salt and black pepper. Heat a griddle pan until smoking, then add the steak, cook for 3-6 minutes each side, or until cooked to your liking. Transfer to a plate and allow to rest for 5 minutes, then thinly slice.
Just before serving, stir the Chinese leaf into the salad ingredients. Divide between 4 plates, place the beef on top and drizzle over remaining dressing. Serve immediately.
Recipe from Thai Taste
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