Heat 1 Tablespoon oil in a medium skillet over medium heat.
Add the ground beef and cook until browned and crumbled, about 6-7 minutes.
Add 4 cloves minced garlic and 1 Tablespoon minced ginger. Cook, stirring, 1-2 minutes until fragrant.
Add 3 Tablespoons soy sauce, 2 Tablespoons brown sugar, 1 Tablespoon rice vinegar, 1 Tablespoon sriracha, 1 teaspoon fish sauce, and 1 teaspoon crushed red pepper flakes. Cook, stirring, until meat has absorbed some of the sauce.
Stir in 4 sliced green onions and 1 teaspoon sesame oil and cook 1 minute more.
Remove from heat; serve over rice and garnish with sesame seeds, additional green onions, sliced cucumbers, carrots, peppers, or garnishes of your choice.