For the waterfall beef, rub the meat in oyster sauce. Cook it under the grill at full temperature for 8 minutes. Juice the limes and lemons. Roughly chop the shallots and spring onions – you don’t want them cut too fine, as you want to achieve a crunchy texture. Mix the shallots and spring onions in a bowl with the fish sauce. Add the lemon and lime juice, dried chilli flakes and leave to marinate. Take the meat out of the grill and let it rest for about 10 minutes. Pour the fat from the meat into the salad for additional flavour. Thinly slice the meat, nice and thinly, and add it to the salad. Mix together and add the fresh herbs, to finish. Serve the salad in a big bowl.

For the garnish, dry roast the rice in a frying pan. Add the lemongrass and kaffir lime. Blend all the ingredients together. Sprinkle the garnish on the meat just before serving.