Flatten chicken to 1/4-in. thickness. In a small bowl, combine 1 teaspoon cornstarch, rice wine vinegar and sesame oil; brush over both sides of chicken. Place in a large resealable plastic bag. Seal bag and turn to coat; refrigerate for 30 minutes., In a small saucepan, bring the brown sugar, water, cider vinegar and lemon slices to a boil. Reduce heat; simmer, uncovered, for 15-20 minutes or until lemon slices are golden brown and sauce is thickened. , Meanwhile, place egg and remaining cornstarch in separate shallow bowls. Dip chicken in the egg, then cornstarch. In an electric skillet, heat 1/2 in. of oil to 375°. Carefully place chicken in hot oil. Cook for 3-5 minutes or until meat is no longer pink. Serve with rice and lemon mixture.