- Mix the beef steaks in 2 tbsp of the oil, sliced garlic, chilli and lemongrass and marinate for 15 mins.
- Place 1 tbsp of the oil in to a pan and cook the steak to the desired level of doneness. Remove from the pan and let it rest while making the sauce.
- Add the last of the oil in to the pan and fry the onions till they start to brown. Add the coconut milk to the pan and let the sauce reach a simmer.
- When the sauce has reached a simmer, add the fish sauce, oyster sauce, tamarind and palm sugar. Stir and continue to simmer until the palm sugar has dissolved fully.
- In a separate bowl, blanch the vermicelli noodles.
- When the sugar has dissolved, remove the pan from the heat and add the Thai basil leaves and mix.
- To serve, spoon the sauce mixture on to a plate, place the vermicelli noodles on top of the sauce, and finish with slices of the steak. Garnish with more basil and chillies.