For the garlic and chilli sauce, place all the ingredients in a small saucepan with two tablespoons water. Bring to the boil, then reduce the heat and simmer for a few minutes until the sugar is dissolved. Set aside to cool.
For the steamed rice, add 500ml/18fl oz water to a pan then add the rice and salt. Cook on a low heat until all the water has disappeared. Place a lid on top and set aside for 20 minutes.
For the chilli crab, heat a wok until hot and add the vegetable oil, ginger, garlic and chillies and stir fry for two minutes.
Meanwhile, whisk the tomato sauce, garlic and chilli sauce, hoisin sauce and fish sauce together in a bowl. Add the sugar and 75ml/2½fl oz water and mix to combine. Add to the wok and bring to the boil.
Add the crab then reduce the heat and simmer for 3-4 minutes until the sauce has thickened slightly and the crab is heated through.
To serve, place a softened banana leaf on each serving plate and spoon on the crab and the rice next to it. Garnish with chopped coriander.