Use a sharp knife to score the skin on the duck breasts lightly, cutting down into the fat but not through to the meat.
Heat a frying pan until very hot, then add the duck breasts, skin-side down, and cook for 3 minutes or until sealed and browned. Turn over and cook for 2 minutes. Use a slotted spoon to transfer the duck breasts to a baking sheet, skin-side up.
In a small bowl, mix together the soy sauce, honey, ginger and chilli powder. Spoon over the duck. Cook in a preheated oven, 200°C (400°F), Gas Mark 6, for 6–9 minutes, until cooked to your liking. The duck may be served pink in the centre or more well cooked.
Meanwhile, in a bowl, mix together all the ingredients for the salsa and season well with salt and pepper.
Thinly slice the cooked duck and fan out the slices slightly on individual plates. Spoon some of the salsa over the duck and serve immediately, offering the remaining salsa separately.