Mix cornstarch with 2 tbsp water in a small bowl. Set it aside for now.
Combine soy sauce, honey, and sesame oil in another small bowl. This is your sauce.
Heat 1 tbsp vegetable oil in a large skillet or wok over medium-high heat until it shimmers.
Sear the beef strips for 2-3 minutes per side until they're browned outside but still pink inside. You're not cooking them through yet. Remove and set aside on a plate.
Add the remaining 1 tbsp oil to the same skillet. Toss in your minced garlic and grated ginger.
Cook garlic and ginger for about 30 seconds until fragrant. Don't let them burn.
Add your sliced onion and broccoli florets. Stir constantly for about 3-4 minutes.
The broccoli should turn bright green and still have some crunch. You want crisp-tender, not soft.
Pour in your sauce mixture and stir everything together for about 1 minute.
Add the cornstarch slurry and stir it all in. The sauce will thicken up in about 30 seconds.
Return the beef to the skillet and toss everything together for another minute.
Sprinkle sesame seeds on top and add salt and black pepper to taste. Done.
