Step 1: Prepare the Beef

Slice the beef against the grain into thin strips. Cutting against the grain ensures that the meat remains tender rather than chewy. Place the sliced beef into a bowl and add the soy sauce, cornstarch, black pepper, and baking soda. Mix thoroughly, ensuring every piece is coated, and let it marinate for at least 15 minutes. This marinade helps tenderize the meat and enhances its flavor.

Step 2: Make the Stir-Fry Sauce

In a separate bowl, combine the oyster sauce, soy sauce, water, cornstarch, brown sugar, and black pepper. Whisk everything together until smooth. This step ensures that the cornstarch is evenly distributed, preventing lumps from forming in the sauce. Set aside.

Step 3: Cook the Beef

Heat one to two tablespoons of oil in a large pan or wok over medium-high heat. Once the oil is hot, add the marinated beef in a single layer. Use a spoon or tongs to separate the pieces so they do not overlap. Let the beef cook for about two minutes on one side before flipping to ensure even browning. Once all sides are browned and the meat is cooked through, remove it from the pan and set aside.

Step 4: Blanch the Broccoli

Bring a pot of water to a boil. Add the broccoli florets and cook for exactly two minutes. This quick boiling method, known as blanching, preserves the vibrant green color and ensures the broccoli remains crisp. Drain the broccoli and set it aside. If a firmer texture is preferred, steaming the broccoli for three to four minutes is a good alternative.

Step 5: Sauté the Garlic

Return the pan to the stove over medium heat and add a little more oil. Add the minced garlic and stir it around the pan for about 30 seconds or until it becomes fragrant. Be careful not to let the garlic burn, as it can develop a bitter taste.

Step 6: Thicken the Sauce

Pour the prepared stir-fry sauce into the pan with the garlic. Stir continuously as the sauce begins to heat up. Once it starts to thicken, reduce the heat slightly to prevent burning. The cornstarch in the sauce will create a glossy, smooth texture that coats the ingredients evenly.

Step 7: Combine Everything

Add the cooked beef and blanched broccoli to the pan with the sauce. Stir everything together until the beef and broccoli are well coated. Allow the mixture to cook for an additional one to two minutes, ensuring that the ingredients absorb the flavors of the sauce.

Step 8: Serve and Enjoy

Turn off the heat and transfer the beef and broccoli to a serving dish. This dish pairs well with steamed white rice, brown rice, or noodles.