Heat the oil in a hot pan and fry the garlic, spring onions, lemongrass, ginger and chilli together until aromatic. Remove from the pan and fry the mince until crumbly, breaking up the meat with a spatula as you stir-fry. Add the cooked garlic mixture and the rest of the seasoning, and stir-fry until the meat is browned and caramelised.
To Serve: Sprinkle with peanuts and coriander and provide crispy lettuce leaves as cups. Drizzle lime juice over each bite before eating.