Step 1: Make the Meatballs

1. Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper or lightly grease it.
2. In a large bowl, combine the ground meat, breadcrumbs, egg, minced garlic, green onions, soy sauce, sesame oil, grated ginger, black pepper, and sugar.
3. Mix until well combined but avoid overmixing to keep the meatballs tender.
4. Shape the mixture into 1-inch meatballs and place them on the prepared baking sheet.
5. Bake in the preheated oven for 15-18 minutes, or until cooked through and lightly browned.

Step 2: Prepare the Korean BBQ Sauce

1. While the meatballs are baking, prepare the sauce. In a small saucepan, combine soy sauce, honey or brown sugar, sesame oil, minced garlic, grated ginger, gochujang, and rice vinegar.
2. Heat the mixture over medium heat, stirring occasionally, until it begins to simmer.
3. If you prefer a thicker sauce, mix the cornstarch with water to create a slurry, then stir it into the sauce. Cook for 1-2 minutes until thickened.
4. Remove from heat and set aside.

Step 3: Make the Spicy Mayo Dip

1. In a small bowl, whisk together the mayonnaise, sriracha, lime juice, and honey until smooth.
2. Taste and adjust the spice level by adding more sriracha if desired.
3. Cover and refrigerate until ready to serve.

Step 4: Glaze the Meatballs

1. Once the meatballs are cooked, transfer them to a large bowl.
2. Pour the Korean BBQ sauce over the meatballs and toss gently to coat evenly.

Step 5: Garnish and Serve

1. Transfer the glazed meatballs to a serving platter.
2. Garnish with sesame seeds and sliced green onions for a pop of color and flavor.
3. Serve warm with the spicy mayo dip on the side.