3 tablespoons unsalted butter
1 sweet onion, diced
3 carrots, peeled and diced
2 celery sticks, diced
3 garlic cloves, minced
kosher salt and pepper
½ teaspoon poultry seasoning
1 ½ cups cooked, shredded chicken
6 cups chicken stock
1 parmesan cheese rind
1 cup uncooked orzo pasta
½ cup milk
1 teaspoon all-purpose flour
3 tablespoons fresh parsley, plus more for topping
parmesan cheese, for topping
lemon wedges, for spritzing