01 - Preheat oven to 425°F. Line a baking sheet with parchment paper.
02 - In a large mixing bowl, combine ground meat, egg, breadcrumbs, minced garlic, chopped spring onions, soy sauce, salt, and black pepper. Gently mix until ingredients are just combined.
03 - Shape the mixture into 20 to 24 small, even-sized meatballs and arrange on the prepared baking sheet.
04 - Bake for 12 to 15 minutes, until meatballs are cooked through and browned.
05 - While meatballs are baking, combine hot sauce, brown sugar, honey, apple cider vinegar, soy sauce, and sriracha (if using) in a saucepan over medium heat. Stir and bring to a gentle simmer until the sugar dissolves completely.
06 - Reduce heat to low and whisk in butter until melted and sauce becomes glossy.
07 - Transfer baked meatballs to a large bowl. Pour the hot firecracker sauce over them and gently toss to ensure even coating.
08 - Arrange meatballs on a platter, garnish with sesame seeds and sliced spring onions, and serve immediately.