Take your frozen mixed vegetables 30 minutes before cooking. Place it in a colander or bowl. (no need to thaw)
Chop your onion and mince your garlic.
Heat oil in a wok or skillet over medium-high, then add chopped onions and stir for 1-2 minutes, then add the minced garlic.
Then add the ground beef, stirring and crumbling into smaller pieces. Drain excess grease, then add the oyster sauce and stir until mixed.
Add the frozen mixed vegetable and stir to combine. Cover for 2-3 minutes. Then add salt and pepper to taste continue to stir until well combined.
Garnish with green onions and serve over rice, quinoa, or buns.