Preheat Oven:
Preheat oven to 400°F (200°C). Line a baking sheet with parchment paper or lightly grease it.
Cook the Vegetables:
In a skillet over medium heat, sauté mushrooms, onion, and celery in a little olive oil until softened, about 5–6 minutes. Let cool slightly.
Mix the Meatball Base:
In a large bowl, combine ground turkey, sautéed vegetables, cornmeal (or stuffing), dried cranberries, egg, poultry seasoning, garlic powder, salt, and pepper. Mix gently until just combined.
Shape Meatballs:
Roll mixture into 1½-inch balls and place on prepared baking sheet. You should get about 20–24 meatballs.
Bake:
Bake for 20–25 minutes, or until meatballs are cooked through and golden on the outside (internal temp should reach 165°F).
Serve:
Serve hot, garnished with fresh parsley or alongside gravy, cranberry sauce, or mashed potatoes.