- In a small bowl, whisk together the soy sauce, water, brown sugar, ginger, garlic, black pepper, and cornstarch. Set aside.
- In a large nonstick skillet over high heat, heat 1 tablespoon of oil until the pan is hot (oil should shimmer). Add the beef strips and cook, stirring occasionally, until the meat is just about cooked through. Transfer to a plate.
- Add the stir-fry sauce, reduce heat to medium/low, and simmer for 3-4 minutes. It will thicken. Add blanched broccoli and stir to combine.
- Return the beef to the skillet and continue to cook until the beef is cooked through, and the sauce has reduced slightly, about 3 minutes.
- Take the skillet off the heat and serve immediately over rice. Garnish with sesame seeds, if desired.