Peel and finely chop the shallots. Peel and crush or grate the garlic. Halve the chilli. Flick out the seeds and white bits for a milder flavour. Chop finely. Peel and finely chop or grate the ginger. Juice the lime. Fill the kettle and boil it.
Pull the largest leaves from the cabbage - you'll need 4-6. Rinse them. Fill a large pan with boiling water. Add the cabbage leaves. Cook for 2-3 mins till just tender. Drain them. Put to one side.
Tip the rice into a small pan. Pour in 250ml hot water from the kettle. Add a pinch of salt. Cover and bring to the boil. Turn the heat right down. Simmer for 6 mins till all the water has been absorbed. Take off the heat. Steam, lid on, for 2-4 mins till the rice is cooked.
Warm a splash of olive oil in the frying pan. Add the shallots. Stir and fry for 4-5 mins over a low-medium heat till golden. Add the garlic, chilli and ginger. Cook and stir for 1 min.
Add the beef mince to the pan. Stir well to break up any lumps. Fry over a low heat for 8-10 mins till well browned. Stir every so often.
While the beef cooks, peel the mango. Slice the flesh off the stone. Finely chop it. Peel and finely chop the onion. Rinse, dry and chop the tomatoes. Mix the mango, onion and tomatoes together in a bowl with half the lime juice. Season.
Add 1 tbsp of the tamari, 1 tbsp Demerara sugar and the rest of the lime juice to the beef. Taste to check the seasoning. Add more tamari if you think it needs it.
Pile the rice and the beef larb into the cabbage leaf cups. Serve with the mango salsa.