To prepare chicken: heat oil in large nonstick skillet over med-high. Add ginger and garlic; saute 15 seconds. Add carrot, zucchini and bell pepper; saute 3 min or til crisp-tender. Add 1 T soy and 2 t hoisin sauce; saute 30 seconds. Place in a bowl and let cool 5 minute Stir in panko.
Slice each breast half lengthwise, cutting to but not through, other side. Open halves, laying breast flat. Place each breast half between 2 sheets heavy plastic wrap and pound til 1/4 inch thick.
Divide carrot mixture into 4 equal portions; spoon each portion down center of each breast half, leaving a 1/2 inch border down center at each end. Fold sides over filling.
Place a 2 foot long sheet heavy duty plastic wrap on a work surface with 1 long side hanging over the counters edge 2 inches. Place a stuffed breast half, seam side down on the end farthest from you; tightly roll the chicken towards you, jelly-roll fashion. Twist the ends in opposite directions to form a cylinder. Tie plastic wrap in knots against chicken on each end. Trim off excess wrap close to knots. Double wrap the chicken roll using the same procedure. Repeat with remaining breast halves.
Bring three quarts of water to boil in a large stockpot; add wrapped chicken. Simmer 15 min (DO NOT BOIL), turning occasionally. Remove from water, and let stand 10 min before unwrapping and cutting into 1/2 inch thick slices.
For sauce: Combine onions, vinegar, 1 T soy, 2 t ginger, 2 t honey, and 5 t hoisin in a small bowl. Serve with chicken.