01 - Set your oven to 400°F (200°C) and line a baking sheet with parchment paper.
02 - In a large bowl, gently combine the ground meat, breadcrumbs, egg, milk, grated onion, minced garlic, soy sauce, salt, and black pepper. Be careful not to overmix. Shape the mixture into 20-24 small meatballs.
03 - Arrange the formed meatballs on the prepared baking sheet and bake them for 15-18 minutes, or until they are nicely browned and cooked through.
04 - While the meatballs are baking, combine the cream soda, ketchup, soy sauce, brown sugar, apple cider vinegar, Worcestershire sauce, and smoked paprika in a saucepan. Bring the mixture to a simmer over medium heat and cook, stirring occasionally, for 8-10 minutes until the sauce has thickened.
05 - Once the meatballs are baked, transfer them directly into the saucepan with the BBQ sauce. Toss well to ensure they are evenly coated. Allow them to simmer for another 2-3 minutes to allow the flavors to meld.
06 - Toss the apple wedges with lemon juice to prevent them from browning before assembly.
07 - Divide the cooked rice, the saucy meatballs, and the prepared apple wedges among four bento containers. If using, sprinkle sesame seeds over the rice and add fresh salad greens or blanched broccoli florets.
08 - Allow the assembled bento boxes to cool slightly before sealing them.