For the dressing, clean and wash the chilli and chop finely with the seeds. Mix with the remaining ingredients until the sugar has dissolved.
For the salad, wash the cucumber, cut in half lengthwise and cut diagonally into thin slices. Wash and halve the tomatoes. Peel and halve the red onion and cut into thin strips. Clean and wash spring onion and cut into fine rings and strips.
Remove the outer leaves from the lemon grass. Cut the lower third of the stalks into fine rings. Halve chillies lengthwise, remove seeds, wash and cut lengthwise into thin strips. Wash herbs, shake dry, pluck leaves and chop coarsely.
Dab steak dry, rub with Ketjap Manis, season with salt. Heat the oil in a pan. Fry the steak for about 1 minute on each side, then continue to fry for about 3 minutes on each side for a pink steak (medium).
Cut the steak into slices and mix half of it with the prepared salad ingredients and dressing. Arrange the other slices on plates and place the salad on top. Sprinkle with a large pinch of roasted rice if desired.
Plus jasmine rice.