1. Prepare the Beef

Start by slicing your beef into thin strips, cutting against the grain. This is essential for ensuring that the beef is tender after cooking. The strips should be about 1/4 inch thick for the best texture. After slicing, place the beef in a bowl and coat it lightly with 1 tablespoon of cornstarch, tossing to ensure an even coating. This will help create that crispy exterior when the beef is fried.

2. Make the Sauce

In a small bowl, whisk together the soy sauce, hoisin sauce, rice vinegar, brown sugar, and chili paste (or sriracha if you prefer heat). This combination of savory, sweet, and tangy flavors is the key to creating the authentic Beijing Beef sauce. If you like it sweeter, feel free to add a little extra brown sugar, and for a spicier kick, increase the amount of chili paste or sriracha.

In a separate small bowl, mix the 1 tablespoon of cornstarch with 1 tablespoon of water to create a cornstarch slurry. This will be added later to thicken the sauce and give it a glossy texture.

3. Fry the Beef

Heat the vegetable oil in a large skillet or wok over medium-high heat. Once the oil is hot, carefully add the beef strips in a single layer. It’s best to fry the beef in batches to avoid overcrowding the pan, which could prevent it from becoming crispy. Fry the beef for 2-3 minutes, turning occasionally, until it is golden brown and crispy. Remove the beef from the pan and set it aside on a paper towel-lined plate to drain any excess oil.

4. Cook the Vegetables

In the same skillet, add the sliced onion, bell pepper, garlic, and ginger. Stir-fry the vegetables for about 2-3 minutes, or until they are tender but still crisp. The garlic and ginger will release their aromatic flavors, adding depth to the dish.

5. Combine the Beef and Sauce

Once the vegetables are cooked, return the crispy beef to the skillet. Pour the prepared sauce over the beef and vegetables, stirring to coat everything evenly. Allow the sauce to simmer for 2-3 minutes. This gives the sauce a chance to thicken and infuse the beef and vegetables with flavor.

6. Thicken the Sauce

Once the sauce has simmered, add the cornstarch slurry to the skillet, stirring constantly. The sauce will quickly thicken, becoming glossy and perfect for coating the beef and vegetables. Continue cooking for an additional 1-2 minutes until the sauce reaches your desired consistency.

7. Garnish and Serve

Remove the skillet from the heat and garnish the Beijing Beef with sliced green onions and a sprinkle of sesame seeds (optional). Serve immediately over steamed rice, noodles, or with a side of stir-fried vegetables for a complete meal.