Fill medium skillet with salted water; bring to boil. Add chicken breasts, cilantro sprigs, and whole green onion; reduce heat to medium and poach chicken until just cooked through, about 20 minutes. Using tongs, transfer chicken to plate; cool. Add snap peas to same skillet; increase heat to high and cook until crisp-tender, about 1 minute. Drain; rinse snap peas under cold water to cool. Discard whole green onion and cilantro sprigs. Coarsely shred chicken. Toss chicken, chopped cilantro, chopped green onions, snap peas, and next 3 ingredients in large bowl. Whisk ponzu, vinegar, oil, and ginger in small bowl. Add dressing to salad; toss to coat. Season to taste with salt and pepper. * Available in the Asian foods section of some supermarkets and at Asian markets.