Cut the meat into bite-sized cubes or thin slices. Mix the marinade, pour over the meat, and marinate for 20 minutes.
Meanwhile, prepare the vegetables – chop the garlic; slice the onion; deseed the chilli & chop it finely. Remove the outer layer of lemongrass, cut it in half then smash flat with a knife or tenderiser.
Heat a wok over medium flame. When it is hot, add the oil, then the turkey pieces and stir-fry for 3 minutes. Add the other ingredients (expect the fresh herbs), and stir-fry for about 5 minutes, until the turkey is golden and cooked through.
Add the fresh herb leaves, stir through, then serve immediately.