Prepare all ingredients by chopping the mixed vegetables and mincing the garlic and ginger.
Heat the vegetable oil in a large skillet or wok over medium-high heat.
Add ground beef to the skillet and cook until browned, breaking it apart with a spatula, approximately 5-7 minutes. Drain excess grease if necessary.
Stir in the minced garlic and ginger, cooking for another 1-2 minutes until fragrant.
Add the mixed vegetables to the skillet and cook for about 3-4 minutes until they are tender but still crisp.
Pour in the soy sauce and oyster sauce, stirring well to combine. Continue cooking for an additional 2-3 minutes to allow the flavors to meld.
Drizzle with sesame oil and season with salt and pepper to taste.
Serve immediately over cooked rice.
Feel free to customize the mixed vegetables according to your preference or seasonal availability.
For a bit of heat, you can add red pepper flakes or a dash of Sriracha to the sauce.
This dish can also be made ahead of time and stored in the refrigerator for up to 3 days. Reheat before serving.