For the sauce, whisk together all ingredients from beef broth to cornstarch. Set aside.
Heat wok on medium high and add oil. Once hot, add broccoli and season with salt and pepper. Cook 3-5 minutes, until tender and beginning to brown. Remove from pan.
Add ground beef and diced onion and cook, breaking beef apart into small pieces until fully browned (~5 min). Season with more salt and pepper.
Add cooked broccoli to the pan along with the sauce (whisking again if any separation occurred). Cook until sauce thickens, stirring everything together.
Garnish with green onion and serve over rice, if desired. Enjoy!
