Beef and Broccoli Stir-fry

2 Tablespoons soy sauce
1 Tablespoon rice wine vinegar
1 Tablespoon sugar
½ Teaspoon sesame oil
2 ½ Teaspoons cornstarch
1 Clove minced garlic
1 Teaspoon grated fresh ginger
¾ Pound thinly sliced beef*
1 Medium head broccoli cut into
2 Tablespoons vegetable oil
2 Tablespoons vegetable oil
½ Cup chicken stock
2 Tablespoons oyster-flavored sauce Make a marinade for meat by mixing the sugar, sesame oil, into medium bowl.Mix in cornstarch until smooth.Add ginger and garlic.Immerse beef and cover with plastic wrap.let set 30 minutes at room temperature.Heat wok add 2 tablespoon oil and coat sides.Stir-fry meat for 2-4 minutes until well browned. Use slotted spoon to transfer meat to plate. Immediately add broccoli and chicken stock. Cover pan and cook until crisp. Uncover pan and stir in meat and oyster sauce