Preheat the oven to 400°F (200°C) and line a baking sheet with parchment paper.
In a large bowl, combine the ground beef (or turkey), breadcrumbs, grated Parmesan, chopped parsley, minced garlic, egg, salt, black pepper, and red pepper flakes (if using). Mix until all ingredients are evenly combined.
Shape the mixture into meatballs, about 1 inch in diameter, and place them on the prepared baking sheet.
Bake the meatballs in the preheated oven for 20-25 minutes or until they are cooked through and golden brown.
While the meatballs are baking, prepare the glaze. In a small saucepan, combine the sweet chili sauce, soy sauce, honey, rice vinegar, and sesame oil. Heat over medium heat until it starts to simmer, then reduce the heat and let it cook for about 5 minutes, stirring occasionally.
Once the meatballs are done, remove them from the oven and transfer them to a large bowl. Pour the sweet chili garlic glaze over the meatballs and toss gently to coat all the meatballs evenly.
Serve the glazed meatballs hot, garnished with additional parsley if desired.
Notes
Serve the meatballs on a large platter drizzled with extra glaze, and sprinkle some sesame seeds and chopped green onions on top for vibrant color and flavor.