Preheat your oven to 450°F (232°C) and line a baking sheet with parchment paper or aluminum foil.

In a large mixing bowl, combine the ground beef, chopped green onions, minced ginger, minced garlic, kosher salt, and pepper. Mix until fully incorporated and form into tablespoon-sized meatballs.

Rinse the broccoli florets under cold water, then toss them with olive oil, kosher salt, and pepper. Arrange them on the baking sheet next to the meatballs.

Bake the meatballs and broccoli in the preheated oven for 15 minutes until cooked through and golden brown.

In a medium skillet, heat vegetable oil over medium-high heat. Add soy sauce, brown sugar, minced garlic, minced ginger, water, rice wine vinegar, and red pepper flakes. Let simmer for 10 minutes until thickened.

Whisk cornstarch with ½ cup of water until smooth, then stir into the sauce and cook for another minute until thick.

Carefully transfer the baked meatballs to the skillet with the sauce and toss until well-coated.

Serve over rice or noodles, garnished with sliced green onions and sesame seeds.