Heat 2 tablespoons of oil in a pan, add the onions and fry slowly for 3 minutes, stirring often. Add the marsala (sherry) and cranberries, stir and cook for 1-2 more minutes. Remove from the heat and set aside to cool.
Meanwhile place the torn bun in a food processor and drizzle over the milk. Add half of the meat, sage, parsley, nutmeg, onion granules and seasoning and pulse until the mixture becomes sticky (do not overblend).
Transfer the mixture into a large bowl, add the rest of the turkey meat, chestnuts, onion mixture (once cooled) and stir thoroughly to combine.
Form good size meatballs (sprinkle some water on your hands when doing this step) and roll them in flour or breadcrumbs.
Heat up a little oil in a large frying pan (2-3 tablespoons per batch) and fry the stuffing meatballs over a low heat for 6-8 minutes until lightly browned, turning often (take care not to burn them). Serve immediately (see the post for serving suggestions).
Notes
Meat: I used lean ground turkey (approx. 7% fat), but you could use ground lean pork instead. I do NOT recommend using white meat (i.e. turkey breast or pork tenderloin) is the meatballs would be too dry.
Herbs: I used a combination of fresh parsley and sage but you could also add a bit of rosemary and thyme into the mixture. If you prefer using dried herbs add approx. 1.5 teaspoon of each.
Bread: I added a very soft bun into the mixture in order to make soft, fluffy stuffing meatballs. Using breadcrumbs doesn't produce the same effect so I don't recommend them in this recipe.
Coating the stuffing balls: Use either flour or fine breadcrumbs.
Frying: It is important to fry these stuffing balls slowly, over a low heat so they cook through while not getting too brown too quickly. For best results fry use a non-stick large frying pan and turn these balls over several times. Do not overcrowd the pan - fry in batches.
Best served immediately. Reheat leftover stuffing balls either in a microwave or in the oven.