In a bowl, combine the beef sirloin slices with 2 teaspoons of cornstarch, a tablespoon of soy sauce, and a drizzle of sesame oil. Mix well to ensure the beef is evenly coated. Let it marinate for about 15-20 minutes while you prepare the other ingredients.
In a separate bowl, whisk together the remaining soy sauce, water, brown sugar, and minced garlic and ginger. Set this sauce aside as you continue with the recipe.
Heat 1 tablespoon of canola oil in your wok or skillet over medium-high heat. Once hot, add the marinated beef in a single layer. Allow it to sear without moving it for about 2 minutes, then stir-fry until it’s just cooked through, approximately 3-4 minutes. Remove the beef from the pan and set it aside.
In the same pan, add another tablespoon of canola oil. Toss in the broccoli florets and sauté for about 2 minutes. Add 3 tablespoons of water to the pan, cover, and steam for an additional 2-3 minutes, or until the broccoli is bright green and tender-crisp.
Return the cooked beef to the pan with the broccoli. Pour in the prepared sauce, stirring to coat the beef and broccoli evenly. Let it cook together for another 2-3 minutes until the sauce thickens slightly.
Remove the pan from heat. Serve immediately, garnishing with sliced green onions, a sprinkle of sesame seeds, and fresh cilantro if desired. Enjoy your Broccoli Beef over steamed rice or noodles for a complete meal!
