Preparation / Directions:
1. Combine all the sauce ingredients-except the cornstarch and arrowroot-in a small saucepan over high heat. Stir often while bringing mixture to a boil. When sauce reaches a boil, remove it from heat and allow it to cool a bit, uncovered.
2. Slice chicken breasts into bite-size chunks. Remove exactly 1 cup of marinade from pan and pour it over chicken in a large resealable plastic bag or other container that allows the chicken to be completely covered with marinade. Chicken should marinate for at least a couple of hours. Cover the remaining sauce and leave it to cool until the chicken is ready.
3. When chicken has marinated, preheat 2 inches of vegetable oil in a wok or skillet to 350 degrees.
4. Combine cornstarch with arrowroot in a small bowl, then add 3 tablespoons of water. Stir until cornstarch and arrowroot have dissolved. Pour this mixture into sauce and set pan over high heat. When sauce begins to bubble and thicken, cover and remove it from heat.
5. Beat together ice water and egg in a medium bowl. Add baking soda and salt.
6. Add 3/4 cup of the flour and stir with a fork just until the flour is blended into the mixture. The batter should still be lumpy.
7. Sprinkle another 1/4 cup of flour on top of batter and mix with only one or two strokes. Most of the new flour will still be floating on top of the mixture. Put the remaining flour (1/2 cup) into a separate medium bowl.
8. Dip each piece of chicken first into the flour, then into the batter. Let some of the batter drip off, and then slide the chicken into the oil. Fry up to 1/2 of the chicken pieces at a time for 3-4 minutes, or until golden brown. Flip the chicken over halfway through cooking time. Remove chicken to a rack or paper towels to drain.
9. As chicken cooks, reheat the sauce left covered on the stove. Stir occasionally.
10. When all the chicken is done, pour it into a large bowl, and cover with thickened sauce. Stir gently until all of the pieces are well coated.