Combine lemon juice, crumbled stock cubes, cornflour, honey, brown sugar, ginger and water in a saucepan; stir over a low heat until sauce boils and thickens.
Carefully remove skin from chicken breasts. With a sharp knife, remove chicken breasts from bone, giving eight individual pieces.
Pound chicken breasts out lightly.
Put cornflour into bowl and gradually add water, lightly beaten egg yolks and salt and pepper, mixing well. Dip chicken breasts into this batter and drain well. Put a few pieces of chicken into deep hot oil; fry until lightly golden brown and cooked through. Drain on absorbent paper. Keep warm while cooking remaining chicken.
Slice each cooked chicken breast across into three or four pieces. Arrange on serving plate, sprinkle with chopped shallots and spoon hot sauce over.