Slice the beef against the grain into long, thin strips, a little thinner than ¼ inch thick. The thinner you slice the beef, the more tender it will be. Transfer the beef to a large mixing bowl.
Marinate the beef
Add the soy sauce, salt, black pepper, sesame oil, neutral oil, and potato starch to the beef. Add the water little by little, up to 3 tablespoons, while gently massaging the marinade into the beef.
The beef should look plump, juicy, and a brighter red once it absorbs the marinade. There should be no pool of liquid at the bottom of the bowl. Toss gently to help the beef absorb the marinade. Cover and set aside for 20 to 30 minutes, or refrigerate overnight.
Make the ginger scallion oil
In the meantime, dice the scallions into small rounds and grate the peeled ginger. Place both in a heatproof bowl. Add the sesame oil, salt, white pepper, and Sichuan peppercorn powder, if using.
In a small saucepan, heat the avocado oil over medium-low heat for about 7 to 8 minutes, or until the oil is hot and shimmering. To test, insert a dry chopstick into the oil. If small bubbles form around it, the oil is ready.
Carefully pour the hot oil over the scallions and ginger. It should sizzle right away. Stir to combine and let the scallions soften for a few minutes.
Line a large rimmed baking sheet with foil and lightly drizzle the bottom with oil.
Take one strip of beef, fold it in half, and thread one end onto the skewer. Keep threading the strip back and forth until it is secured. This helps keep the beef from falling off.
Gently push the beef down, then repeat with the remaining pieces. Leave about 1 to 1½ inches of space at the top of each skewer. Pack the beef snugly, but not too tightly.
You’ll have a few small pieces of beef here and there because the beef is sliced thin. Just thread them onto the skewers with the larger pieces.
Place the skewers on the prepared baking sheet. Lightly season them with a little salt and pepper, then drizzle a little oil directly over the skewers.
Cooking methods
Oven broiler [recommended method]
Preheat the broiler for 5 to 6 minutes. Place the skewers on a foil-lined sheet pan and set the pan on the top rack, about 3 to 4 inches from the heating element.
Broil for 3 to 4 minutes per side, about 6 to 8 minutes total. Watch closely so the beef does not burn.
Do not line the sheet pan with parchment paper. The tray sits close to the heat source, and parchment can burn and cause smoke.
Air fryer
Spray the air fryer basket with oil before adding the skewers. Air fry at 400°F for 7 minutes. No need to flip.
Oven bake
Preheat the oven to 425°F. Place a greased wire rack over a foil-lined sheet pan. Arrange the skewers on the rack.
Bake on the middle rack for 8 to 10 minutes total, flipping halfway through. Check at the 5-minute mark.
How to serve
Let the skewers rest for 2 to 3 minutes. Transfer them to a serving plate. While the beef is still hot, spoon a few tablespoons of ginger scallion sauce over the skewers. Serve warm.
Notes
Cooking method notes
In my recipe testing, all three cooking methods gave the beef a good flavor and a tender texture. For the best grilled-style flavor and color, the oven broiler and air fryer are my favorites.
The broiler gave me the best result because the beef was less likely to overcook compared to the air fryer. The beef also picked up better color and a lightly charred edge.
The oven-baked method is my least favorite. The beef still tastes good, but it does not have the same grilled-style flavor, and the color is not as nicely charred.
If using the oven-bake method: Use a wire rack over the sheet pan. The rack allows heat to circulate under the beef, similar to the airflow in an air fryer. It also keeps the beef from sitting in its own juices, so the skewers roast instead of steam.
Why add water little by little to the beef marinade
This comes from the Chinese velvet beef technique. The beef absorbs the seasoning liquid and water, which helps the texture stay plump and juicy.
Add the water little by little and massage it into the beef. There should be no liquid sitting at the bottom of the bowl. The liquid should be fully absorbed before you add more.
Make-ahead:
Beef: You can slice and marinate the beef up to 1 day ahead and store it in the fridge. You can also freeze the marinated beef for up to 1 month.
Ginger Scallion Sauce: Make the sauce ahead and store it in an airtight glass container in the fridge. It lasts up to a month but is best used within 2 weeks for the freshest flavor.
Reheat:
Beef: Air fry at 360°F for 3 to 4 minutes, or pan-grill over a hot pan for a few seconds per side.
Ginger scallion sauce: Do not reheat the sauce in a microwave as the oil will cause splatter. The sauce tastes great at room temperature. Simply place the sauce jar in a cool and dry kitchen counter until the oil returns to room temperature. Use and serve as you wish and always use a clean spoon to scoop the sauce.