Combine the oyster sauce, fish sauce and brown sugar. Pour the mixture over the steaks and use your fingers to massage the marinade all over the steak pieces. Allow to marinate while you prepare the remaining ingredients.

For the spicy dipping sauce, toast the rice in a dry frying pan over high heat until golden brown and fragrant (it should smell like popcorn). Use a mortar and pestle or a spice grinder to grind to a fine powder. In a bowl, combine the tamarind, fish sauce, lime juice, sugar, chilli flakes and toasted rice powder. Mix until well combined. Then stir through the shallot and coriander. Transfer to a small serving bowl and set aside until ready to serve.

Heat a large heavy-based frying pan over high heat. Brush with oil. When hot, add the steaks and cook for 2-3 minutes, turning the steaks every so often until you get a nice charred colour. Then turn the heat to low and continue cooking (and flipping the steaks) for another 2-3 minutes (for medium rare) or until cooked to your liking. Before slicing, transfer to a cutting board and allow to rest for 3 minutes.