- Cut chicken into thin strips; coat with mixture of 1 Tbsp. each cornstarch and soy sauce, sherry and 1/2 teaspoon garlic. Let stand 10 minutes.
- Meanwhile, combine remaining 1 Tbsp. cornstarch and 2 Tbsp. soy sauce, peanut butter, vinegar and sugar; slowly blend in 2/3 cup water.
- Heat 1 Tbsp. oil in hot wok or large skillet. Add chicken and stir-fry 2 minutes; remove.
- Heat remaining 1 Tbsp. oil in same pan. Add green onions, bell pepper and 1/2 teaspoon remaining garlic; stir-fry 2 minutes. Add bean sprouts; stir-fry 1 minute longer. Stir in chicken and peanut butter sauce mixture. Cook until sauce boils and thickens, about 1 minute, stirring frequently.
- Arrange over noodles and sprinkle with peanuts. Serve immediately.