Combine the sauce ingredients in a small bowl, stirring until the sugar and cornstarch is dissolved. Set aside.
Heat the wok over high heat and add the oil. Once very hot, working quickly add the beef and fry, searing all sides, for 1-2 minutes. Add the carrots, garlic and ginger and fry for another minute. Add the remaining vegetables and fry for another minutes. Do not over-cook, you want the vegetables to retain some "crunch." Stir in the sauce and simmer for 1 minute then remove from heat.
Serve immediately with steamed rice.
Recipe by The Daring Gourmet at https://www.daringgourmet.com/beef-stir-fry-with-snow-peas-and-mushrooms/