In a blender or mini-food processor, combine peanut butter, sugar, water, lime juice, soy sauce, sesame oil, and pepper flakes. Pulse until well blended and set aside. Heat oil over medium high heat in a wok. Add the vegetables and garlic, and stir-fry for 4 minutes, or until tender crisp. At this point, I drizzled the hot sesame oil over it. Remove from heat, place in a large bowl, and pour dressing over it. Mix well and serve. This can be served either hot or cold. Either way, I promise it's excellent!