Marinate chicken with salt, caster sugar, pepper, sesame oil and Shaoxing wine. Place in refrigerator for 4-5 hours or overnight.
Take both marinated fillets out and let stand till they reach room temperature.
Whisk egg whites until frothy. Dip chicken into the egg whites and into the cornflour and tapioca flour mixture.
Fry each side for about 3-5 minutes (depending on the thickness and size of the fillets) until golden brown.
Drain on wire rack and let them rest while you prepare the yuzu sauce.
Combine yuzu juice, lemon zest, chicken stock, white vinegar, sweet sherry and caster sugar into a saucepan and heat over low heat until sugar dissolves.
Taste sauce and adjust accordingly (more sugar or yuzu juice to balance the sweetness and sourness).
Add in slurry and stir for another 1-2 minutes until the sauce thickens. Add in cucumber chunks and turn heat off. Set sauce aside.
Slice chicken into strips and arrange on plate. Pour yuzu sauce over and garnish with shredded carrots, sliced red chillies and micro herbs. Serve immediately.