In a large skillet over medium-high heat, brown the ground beef until fully cooked. Drain any excess fat if needed.
Add the broccoli florets to the skillet with the beef and stir-fry for about 3 to 4 minutes, until just tender.
In a small bowl, whisk together the soy sauce, water, cornstarch, brown sugar, garlic, and ginger.
Pour the sauce over the beef and broccoli, stirring constantly until it thickens and coats everything, about 2 to 3 minutes.
Remove from heat and serve over warm rice.
Garnish with sesame seeds and chopped green onions if you’re feeling extra fancy.