Preheat the oven to 350 degrees F. Lightly grease 2 muffin tins, set aside.

Brown the sausage in a large skillet over medium-heat, breaking it down with a wooden spoon. Once browned, add the onions, celery, and apple. Cook until soft and translucent, about 8 minutes.

Remove from heat and pour into a large mixing bowl along with the stuffing mix, cranberries, eggs, salt, pepper and as much chicken stock as needed to moisten the mixture. Stir until it comes together.

Using an ice cream scoop, portion out the stuffing into the prepared muffin tins. Bake until golden brown, about 15 to 20 minutes. Remove from oven and allow to cool slightly before serving.