Preheat oven to 425F and line a sheet pan with aluminum foil for easier cleanup; set aside.

To a large bowl add the soy sauce, garlic, honey, brown sugar, sesame oil, rice vinegar, ginger, optional salt, pepper, optional cayenne or red pepper flakes, and whisk to combine.

Add the steak, stir to combine, and let it marinate for 10 to 15 minutes (if you have time and can marinate for up to 1 hour, even better).

Using a tongs or a slotted spoon, transfer the steak to the sheet pan with space in between the pieces; set aside.

Add the broccoli (I use 6 cups because we like a lot of broccoli, use less if desired) to the marinade mixture and give it a quick dunk, you just want to moisten it a bit. Using a tongs or a slotted spoon, transfer the broccoli to the sheet pan, and scatter it in between the steak if possible so food isn’t overlapping too much; reserve the marinade.

Bake for about 10 to 12 minutes, or until the steak is cooked through and the broccoli is fork-tender; rotate pan once midway through baking for more even cooking. Tip - Since the steak is in small pieces, it won't take long to cook through. If you like more medium-rare steak, I'd check at 8 minutes and see how it looks.

While the food bakes, optionally add the reserved marinade to a small saucepan and bring it to a boil over medium-high heat.

Add the cornstarch and cold water to a small bowl, stir to combine, and all the cornstarch slurry to the boiling saucepan, whisking nearly constantly for 30 seconds or until dissolved. The sauce will get very thick quickly because there’s not much quantity. If desired, add about 1/4 to 1/2 cup water as desired for consistency, whisking until incorporated and smooth.

After the beef and broccoli are done, evenly drizzle with the sauce, to taste.

Evenly garnish with optional green onions, optional sesame seeds, and serve immediately.