Pour the milk into a medium saucepan, add in about 1/4 cup of the stuffing and bring to a boil. The starchiness of the stuffing will thicken the stock as it disintegrates in the hot liquid. If there are any stuffing chunks, mash them with a fork along the edge of the saucepan so they can contribute to the thickening. The butter in the stuffing will add to the creaminess of the stock.
If your corn is still on the cobs, strip the kernels off. Reduce the heat of the saucepan to medium heat, and then add in the corn, turkey and green beans. As all the ingredients are simmering together, fold in the mashed potatoes to thicken the chowder even more. Add salt and pepper to taste. After the chowder has been simmering for 5 to 10 minutes, serve it in a bowl and garnish with the extra stuffing.