Tip the rice into a small pan and pour in 300ml boiling water. Add a pinch of salt, pop on a lid and bring to the boil. Once the water is boiling, turn the heat down and gently simmer the rice for 8 mins till all the water is absorbed. Tip the rice into a sieve and leave it to cool a little.
While the rice simmers, trim the root and top 3cm off the leek. Halve it. rinse out any grit and finely slice it. Finely slice the head of Chinese leaf, discarding the thick cores at the root.
Finely slice the chilli, flicking out the seeds for less heat. Peel and grate the ginger and garlic. Crack the egg into a bowl and beat with a fork till it's well mixed.
Set a wok or deep frying pan over a medium heat. Add ½ tbsp oil and pour in the egg. Swirl to coat the base of the pan. Fry for 3-4 mins till the egg is set. Use a spatula or palette knife to lift up one edge and then roll the omelette up. Slide it out of the wok. Set aside.
Add another ½ tbsp oil to the pan with the leek. Stir-fry for 5 mins till the leek is tender and a little caramelised. Add in the Chinese leaf and stir fry for 2 mins to just soften the leaves a little.
Add the chilli, garlic and ginger and stir fry for 30 seconds then tip in the rice and crab meat and stir to mix well with the veg. Cook for 3-4 mins to warm through.
Slice the omelette and add to the wok. Tip in the tamari and brown rice vinegar and stir everything to combine. Warm through for 2 mins, then squeeze over ½ the lime. Spoon into bowls and serve with the remaining lime sliced into wedges for squeezing.