Follow these simple steps to create your delicious and speedy stir-fry:

1. Prepare the Beef: Thinly slice the beef against the grain. This is crucial for tenderness. In a medium bowl, combine the sliced beef with 1 tablespoon soy sauce, 1 teaspoon cornstarch, 1 teaspoon sesame oil, 1/2 teaspoon black pepper, and 1 minced garlic clove. Toss well to coat and set aside to marinate for at least 10-15 minutes while you prepare the vegetables and sauce. This short marination time significantly enhances flavor and texture.
2. Prepare the Stir-Fry Sauce: In a small bowl, whisk together the 1/4 cup low sodium soy sauce, oyster sauce (if using), rice vinegar, honey or brown sugar, 1 teaspoon sesame oil, 1 teaspoon cornstarch, water or beef broth, grated ginger, 1 minced garlic clove, and red pepper flakes (if using). Set aside. Whisking the cornstarch in thoroughly prevents lumps.
3. Prep the Vegetables: Wash and chop all your vegetables into bite-sized pieces. Try to keep them relatively uniform in size for even cooking. Having everything prepped (“mise en place”) is key to a successful and speedy stir-fry.
4. Cook the Beef: Heat 1/2 tablespoon of avocado oil in a large skillet or wok over high heat until it’s shimmering. Add half of the marinated beef in a single layer, being careful not to overcrowd the pan. Cook for 1-2 minutes per side, until browned but still slightly pink inside. Remove the beef from the pan and set aside on a plate. Add the remaining 1/2 tablespoon of oil and cook the second batch of beef in the same manner. Remove and set aside with the first batch. Cooking in batches prevents the beef from steaming and ensures a good sear.
5. Stir-Fry the Aromatics & Hardy Vegetables: To the same skillet (add a touch more oil if needed), add the sliced onion and cook for 2-3 minutes until softened. Add the additional 2 cloves of sliced or minced garlic and cook for another 30 seconds until fragrant. Be careful not to burn the garlic.
   Then, add the harder vegetables like broccoli florets and carrots. Stir-fry for 3-4 minutes until they begin to tender-crisp. You can add a tablespoon of water or broth and cover the pan for a minute if you prefer them slightly softer, faster.
6. Add Softer Vegetables: Add the bell pepper, snap peas (or snow peas), and mushrooms to the skillet. Continue to stir-fry for another 2-3 minutes. The vegetables should be vibrant and crisp-tender, not mushy.
7. Combine and Sauce: Return the cooked beef to the skillet with the vegetables. Give the stir-fry sauce a quick whisk (as the cornstarch might have settled) and pour it over the beef and vegetables. Stir everything together continuously for 1-2 minutes, until the sauce thickens and coats all the ingredients evenly. The heat will activate the cornstarch, thickening the sauce.
8. Serve Immediately: Once the sauce has thickened and everything is heated through, remove from heat. Serve your Speedy Beef & Veggie Stir-Fry immediately over cooked rice or noodles, garnished with toasted sesame seeds, sliced green onions, or fresh cilantro, if desired.