In a large mixing bowl, combine ground beef, breadcrumbs, egg, chopped green onions, minced garlic, grated ginger, soy sauce, sesame oil, and gochujang. Mix gently until just combined.

Roll the meat mixture into uniform balls, about 1 to 1.5 inches in diameter. Place on a parchment-lined baking sheet.

Heat a tablespoon of oil in a skillet over medium-high heat. Add the meatballs in a single layer and sear for 3-4 minutes until browned. Remove and set aside.

In the same skillet, combine soy sauce, brown sugar, rice vinegar, and another teaspoon of gochujang. Stir until smooth to create a glaze.

Transfer the meatballs to a baking dish and pour the glaze over them. Bake at 375°F for 15-20 minutes until cooked through.

In a small bowl, mix mayonnaise and sriracha to create the spicy mayo dip.

Serve the meatballs warm, drizzled with glaze and garnished with sesame seeds and green onions.