Cut chicken into 1-inch pieces. Combine next 3 ingredients and chicken; let stand 15 minutes. Meanwhile, reserving 1/4 cup syrup, drain mandarin oranges. Blend reserved syrup with sweet & sour sauce; set aside. Heat 1 Tbsp. oil in hot wok or large skillet over medium-high heat. Add chicken and stir-fry 2 minutes; remove. Heat remaining 1 Tbsp. oil in same pan. Add snow-peas; stir-fry 1 minute. Add green onions; stir-fry 30 seconds longer. Add chicken, cashews and sweet & sour sauce mixture; cook, stirring, until all ingredients are coated in sauce. Gently stir in mandarin oranges; heat through.