This recipe is easy to make even if you don't have leftover steak. Simply use a firm cut of beef sliced into bite-size pieces, and reverse the steps for coating the beef: sauté the steak in oil first, cooking it an additional 4-5 minutes, then mix and add the cornstarch slurry. Cook for about 1-2 minutes, then remove from the pan and follow the rest of the recipe as directed.