Boil the eggs in a saucepan of water, lower the heat and simmer for 8–10 minutes. Drain, then crack the shells slightly and cool under cold running water. Peel off the shells.
Heat about 7 cm (3 inches) of oil in a wok over a medium heat. The oil is ready when a slice of shallot sizzles when dropped into it. Deep-fry the chillies for a few seconds to bring out the flavour. Drain on kitchen paper.
Deep-fry the shallots for 6–8 minutes until golden brown and crispy. Remove and drain. Lower each egg into the same hot oil and deep-fry for 6–10 minutes or until browned. Remove and drain.
Remove the oil from the wok and add the fish sauce, tamarind purée or lime juice and sugar and stir for 5–6 minutes or until the sugar has dissolved. Taste and adjust the seasoning.
Halve the eggs lengthways and arrange them with the yolk upwards in a serving bowl. Spoon the sauce over them and sprinkle with the crispy shallots and chillies.