Whisk together the
egg white, rice wine, 2 teaspoons of the soy sauce, 1 teaspoon of
the cornstarch and baking soda in a small bowl; pour over beef.
Seal; turn bag to coat beef with marinade. Refrigerate 1-3 hours.
Heat a large saucepan of water to a boil; add broccoli. Cook 30
seconds; drain. Set aside.
Mix remaining teaspoon cornstarch, 1/2
cup water, oyster sauce, remaining 2 teaspoons of soy sauce, sugar
and pepper to taste in a bowl; set aside.
Heat wok over high heat. Add oil; heat until very hot. Add beef
in batches; stir-fry until meat is lightly browned, about 2 minutes.
Remove with slotted spoon to bowl.
Discard all but 2 teaspoons of the oil; heat oil over medium-high
heat. Add garlic. Cook, stirring, until garlic softens, about 30
seconds. Stir in the water-oyster sauce mixture. Add to wok, heat
to a boil; cook 1 minute. Stir beef and broccoli back into wok.
Cook to heat through, about 1 minute.