1.Combine 2 tbs of the fish sauce and 1 tbs of the juice in medium bowl with beef. Toss beef to coat in marinade. Cover and refrigerate 3 hours or overnight.
2.Drain beef and discard marinade. Cook beef on heated oiled grill plate (or grill or grill pan) until cooked as desired. Cover and stand 5 minutes. Slice beef thinly.
3.Meanwhile, combine cucumber, chilli, onion, tomato and herbs in large bowl.
4.Place sugar, soy sauce, garlic, remaining fish sauce and remaining juice in a bowl and mix to combine.
5.Add sliced beef to salad with dressing, toss gently to combine.
Thai basil is available from most supermarkets. Use traditional basil instead if you cannot find any. We used a vegetable peeler to slice the cucumbers thinly into ribbons.
