Mix broth, remaining 1 Tbsp. sherry, remaining 1 Tbsp. soy sauce, vinegar, sugar and cornstarch. Heat 2 tsp. oil in wok or large nonstick skillet over high heat. Add shrimp, peanuts, and pepper flakes; cook til shrimp are nearly opaque, 1 to 2 minutes. Transfer shrimp mixture to a plate.