In a bowl, combine minced beef, sesame seeds, sesame oil, soy sauce, and black pepper. Mix well. Roll into small meatballs. Set aside.
In a large skillet or wok, heat cooking oil over medium-high heat. Saute onion for 1-2 minutes. Stir in garlic and cook for another 1 minute.
Then add all other veggies and cook, while stirring, until softened. This will take about 5-6 minutes.
When ready, push veggies to the side and cook meatballs in the middle of the pan or wok.
Mix meatballs and vegetables. Add teriyaki sauce and stir until well coated and heated through.