Preheat the oven to 180C/350F/Gas 4.
With a sharp knife, score the fat of the duck into a cross-hatch pattern.
Sprinkle the five-spice powder onto the skin of the duck breasts and rub it into the fat well. Season with salt and freshly ground black pepper.
Heat a heavy-based ovenproof frying pan. Don't add oil. Place the duck breasts skin-side down in the hot pan. Season the other side with five-spice powder and salt and freshly ground black pepper. Cook until most of the fat has run out into the pan and the skin has a golden colour (about three minutes).
Turn the duck breasts over and cook the other side for a minute or so.
Place the duck breasts in the oven for 3-5 minutes to finish.
To make the sauce, warm the honey and soy sauce together in a small pan. Bring up to boiling point and let it bubble for a minute or two to reduce. Take off the heat and allow to cool. The sauce should have a syrup-like consistency.
Remove the cooked duck breasts from the oven and leave to rest in a warm place.
While the duck is resting, heat a medium pan of salted water for the noodles.
Meanwhile, cut the white and green parts of the spring onions into slices on the diagonal.
When the water is boiling, add the egg noodles and cook for 3-4 minutes or according to packet instructions.
Drain the noodles and place them in a bowl. Sprinkle in the sesame seeds, drizzle with a few drops of sesame oil and sprinkle with cut spring onions, reserving some for the garnish. Stir together well.
To serve, place the noodles onto a plate. Squeeze over a bit of lime juice. Slice the duck breasts into strips and place next to the noodles. Sprinkle over the remaining spring onion and drizzle over the honey and soy sauce.