Heat the vegetable oil over medium-high heat in a large pan or wok.
Add the thinly sliced beef and cook until browned, about 3-4 minutes.
Stir in the minced garlic and grated ginger, cooking for an additional minute for flavor.
Add the mixed vegetables to the pan and stir-fry for 5-7 minutes, or until they are tender-crisp.
Pour in the soy sauce and teriyaki sauce, stirring to coat the beef and vegetables evenly. Cook for another 2 minutes until everything is heated through.
Serve the stir-fry over cooked rice or noodles, and sprinkle with sesame seeds.
Notes
Slice beef against the grain for tenderness. Don’t overcook vegetables for the best texture.