Cut each chicken breast half lengthwise. Mix egg white and water in a medium glass or plastic bowl. Add chicken; turn to coat both sides and let stand 10 minutes.

Heat oven to 450 degrees. Line a sheet pan with foil. Roll up a piece of paper towel and pour a tiny bit of oil on the foil-covered sheet pan. Use the rolled up paper to spread it around.

Remove chicken from egg mixture; discard egg mixture. Mix flour, baking soda and red pepper in a large resealable plastic bag. Add 1 chicken piece at a time. Seal bag; shake to coat chicken. Use a pastry brush to brush the surface of the chicken pieces with some oil.

Bake uncovered for 20 to 25 minutes or they register 160 on an instant-read thermometer. While chicken is baking, prepare Chinese Lemon Sauce. Let chicken stand 5 minutes; slice each piece into 5 slices. Pour sauce over chicken. Garnish with lemon slices and green onion.

Heat all ingredients except cornstarch and cold water to boiling in 1-quart saucepan, stirring occasionally. Mix cornstarch and cold water; stir into sauce. Cook and stir about 30 seconds or until thickened. Serve warm, or cover and refrigerate up to 2 weeks.