Place the chicken in a gallon plastic zip bag. Combine the soy sauce, sesame oil, salt, and gin and pour over the chicken. Zip up the bag and turn it over to coat the chicken. Let sit for 30 minutes.
While the Chicken Marinates
Place the sugar, vinegar, stock, cornstarch mixed with water, and lemon juice and rind in a small sauce pan. Bring to a boil and cook stirring, until the mixture thickens.
Drain the chicken and discard the marinade. Put the egg whites in a pie plate and beat. Add the chicken to the beaten egg whites and toss to coat. Put the cornstarch in the other pie plate and roll the chicken pieces in it to coat.
Add oil to a skillet to a depth of one-half inch and heat to 350° F. Add the chicken, one piece at a time if necessary, and brown on both sides. Drain thoroughly.
Cut the drained chicken into one-inch crosswise slices and place it on top of the lettuce on a serving platter. If necessary, keep warm in a 200° F oven.
Add the vegetables and pineapple to the sauce. Remove from the heat and stir in the lemon extract. Pour over the chicken.