Preheat oven to 400 degrees F.
Soak the bread in milk until it's absorbed. Then fold together the lamb, onions, mint, parsley, egg, and some salt and pepper in a bowl. Scoop out single servings with an ice cream scooper. Place the meatballs on a baking sheet or muffin tin and bake until they are no longer pink in the middle, 20 minutes. Serve with caramelized onions on top.