01 - Preheat oven to 425°F (220°C). Line a baking sheet with parchment paper.
02 - In a large mixing bowl, gently combine ground meat, egg, breadcrumbs, minced garlic, chopped spring onions, soy sauce, salt, and pepper until just incorporated. Avoid overmixing.
03 - Form the mixture into 20 to 24 evenly sized meatballs and arrange them on the prepared baking sheet.
04 - Bake the meatballs for 12 to 15 minutes, until browned and cooked through.
05 - While the meatballs bake, combine hot sauce, brown sugar, honey, apple cider vinegar, soy sauce, and sriracha in a saucepan over medium heat. Bring the mixture to a simmer, stirring until the sugar dissolves.
06 - Reduce heat to low and stir in unsalted butter until fully melted and the sauce has a glossy finish.
07 - Transfer the cooked meatballs to a large bowl. Pour the hot firecracker sauce over and toss gently to coat each meatball thoroughly.
08 - Arrange the sauced meatballs on a serving platter. Sprinkle with sesame seeds and sliced spring onions before serving immediately.