Preheat the oven to 350°F. Spray a standard 12 cup muffin tin with cooking spray. Set aside.
In a large skillet, melt 2 Tbsp butter. Add celery and onion cooking until softened around 6 minutes. Add garlic, cooking for 1 minute longer. Set aside to cool slightly.
Meanwhile, in a large mixing bowl, pour chicken stock over stuffing. Let sit 5 minutes or just until stuffing has softened and liquid is absorbed.
Add turkey, cooked vegetables, half and half, eggs, Worcestershire sauce, sage, poultry seasoning, salt, lemon pepper and thyme. Mix well.
Divide evenly between muffin cups using a 4 oz ice cream scoop. Brush tops with remaining melted Tbsp butter.
Bake for 25-35 minutes or until internal temperature reaches 165°F. Let stand 5 minutes then serve topped with mashed potatoes and gravy.