In a large bowl, combine soy sauce, brown sugar, honey, minced garlic, grated ginger, sesame oil, and black pepper. Stir until the sugar is dissolved. Add the steak cubes to the marinade, toss to coat, and let them marinate for at least 30 minutes at room temperature (or up to 2 hours in the fridge).
Heat a non-stick skillet or a cast-iron pan over medium-high heat. Add a bit of oil to the pan if necessary to prevent sticking.
Remove the steak cubes from the marinade, allowing excess marinade to drip off. Reserve the marinade for later. Add the steak bites to the hot pan in a single layer. Cook for about 2-3 minutes on each side until browned and cooked to your desired doneness.
Once the steak bites are cooked, remove them from the skillet and set aside. In the same skillet, add the reserved marinade along with the cornstarch. Stir well and cook for 3-5 minutes until the sauce thickens and becomes sticky.
Return the cooked steak bites to the skillet and toss them in the thickened sauce until well-coated.
Transfer the sticky steak bites to a serving platter. Garnish with sliced green onions and a sprinkle of sesame seeds.
Notes
For best results, marinate the steak for up to 2 hours.