Beef Stir-Fry with Bell Peppers and Sesame Seeds

1 tsp toasted sesame seeds
2 tbsp chopped green onions (for garnish)
Salt and pepper, to taste
Instructions:
Marinate the Beef: In a bowl, combine the beef slices with 2 tablespoons of soy sauce, cornstarch, and a pinch of black pepper. Let marinate for 15-20 minutes.
Heat the Pan: Heat 1 tablespoon of vegetable oil in a wok or large skillet over medium-high heat.
Sear the Beef: Stir-fry the beef in batches until browned and just cooked. Remove from the pan and set aside.
Cook Vegetables: Add the remaining oil to the pan. Stir-fry the onion and bell peppers for 2-3 minutes until slightly tender but still crisp.