In a large bowl bring the meats together. Add all the ingredients and mix to combine.
Once the mixture is nice and uniform start shaping the meat into 4 - 6 meatballs.
In a frying pan add the olive oil. Bring this to a medium heat and add the meatballs. Pan fry the meatballs on all sides (about 2-3 minutes each side) then transfer the meatballs to a pot and add the sauce. Cover and cook for 25 minutes.
When the sweet potato is done, carefully remove from oven. Using a fork, dig out two spots on each sweet potato half to place the meatballs but don't discard any of that yummy sweet potato, simply pile it back on once the meatballs are set in place.
Garnish with freshly shaved parmigiano-reggiano cheese and serve.