Slice beef flank steak thinly against the grain. Combine beef with baking soda, soy sauce, Shaoxing wine, and cornstarch. Marinate for 10 minutes.
Heat wok or large skillet over high heat until smoking. Add oil and swirl to coat.
Add marinated beef and cook, stirring constantly, for 2-3 minutes until beef is nearly cooked through.
Push beef to one side of wok. Add minced ginger and garlic to empty space and cook for 30 seconds until fragrant.
Add snow peas and water. Stir-fry for 1-2 minutes until snow peas are bright green and crisp-tender.
Combine beef broth, oyster sauce, sugar, and sesame oil in a small bowl. Pour sauce over beef and vegetables.
Stir everything together for 30 seconds until sauce coats ingredients and thickens slightly. Remove from heat and serve immediately over rice.