Pat the chicken thigh fillets dry with paper towels. Season with salt, pepper, grated ginger and sugar. Mix well.
Grill the chicken fillets, about four minutes per side. Set aside and cool. Cut into strips about half an inch wide.
Break the noodles into four to six pieces. In a small pan, boil the noodles in water until tender. Drain. Dump in a bowl of iced water. Stir gently until cool. Drain well.
In an oil-free frying pan, toast the cashew nuts. Scoop out and set aside.
In the same pan, toast the sesame seeds. Dump on a small plate and set aside.
Heat the cooking oil in the frying pan until fine wisps of smoke float on the surface. Spread the drained noodles in the hot oil and cook until crisp. Scoop out and place on a plate lined with paper towels.
Rinse the lettuce, tear or slice into bite-size pieces and dry in a salad spinner.
Place all the ingredients for the dressing in a small bowl and stir until the sugar is completely dissolved.
In a large mixing bowl, place the lettuce, fried noodles and chicken. Drizzle in about a tablespoon of dressing. Toss lightly. Add the Mandarin orange segments and cashew nuts. Toss again.
Divide the Chinese chicken salad among bowls. Sprinkle with scallions, mint leaves and toasted sesame seeds. Drizzle in a little dressing. Serve with more dressing on the side.