In small bowl, whisk together agave, soy sauce, vinegar, cornstarch, orange peel and red pepper flakes until thoroughly mixed and cornstarch is dissolved. Set aside. Heat oil in wok or large, heavy skillet over medium-high heat. Stir in garlic and ginger; stir-fry until fragrant, about 1 minute. Add bell pepper and snow peas; stir-fry 1 minute until crisp-tender. Add shrimp and green onions; stir-fry until shrimp just turns pink, about 1 minute. Stir in reserved soy sauce mixture; cook and stir until sauce boils and thickens. Serve over cooked rice, if desired.