Yes, oyster sauce is actually made from oyster extract, but rather than tasting fishy, it has a deep, caramelised sweetness. In fact, it's a culinary secret weapon. Here it adds earthiness and umami to a classic beef stir-fry that crosses over from pan to table in a matter of minutes.
Place rice and 310ml (1¼ cups) cold water in a saucepan over medium heat and bring to the boil. Reduce heat to low, cover with a lid and cook for 15 minutes or until cooked through. Set aside, covered, until ready to serve. While rice is cooking, continue with step 2.
Peel and finely chop ginger. Thinly slice mushrooms. Finely chop gai lan stems and roughly chop leaves, keeping stems and leaves separate.
Heat 2 teaspoons vegetable oil in a wok or frypan over medium heat. Add ginger and cook for 3 minutes or until fragrant. Add mushroom and gai lan stems and cook, stirring, for 3 minutes or until golden and softened. Remove from pan.
Heat remaining vegetable oil in the frypan over high heat. Add beef, spreading out in a single layer and cook, tossing the wok, for 2–3 minutes or until starting to colour.
Return mushroom mixture to pan with oyster sauce and sesame oil and cook for 2–3 minutes or until sauce has lightly caramelised. Add gai lan leaves and toss to combine.
Add ¼ teaspoon freshly cracked black pepper and a little salt and stir to combine. Divide rice between bowls and top with beef stir-fry. Sprinkle with sesame seeds to serve.