Heat the butter in a large stock pot over medium-low heat.

Add in the onion, carrots, celery, and garlic with a pinch of salt and pepper; cook, stirring occasionally, until the vegetables soften.

Stir in the garlic cloves and poultry seasoning.

Stir in the shredded chicken.

Add the chicken stock and the parmesan rind; bring to a boil, then reduce to a simmer.

Stir in the orzo pasta; cook uncovered, stirring occasionally, until the orzo is al dente, about 8 minutes.

In a shaker bottle or bowl, shake or whisk together the milk and flour to form a slurry; pour this into the soup and simmer for another 1 to 2 minutes.

Taste and season with more salt and pepper as needed; if the parmesan rind didn’t melt entirely, scoop it out at this point.

Stir in the fresh parsley. Serve immediately with a lemon wedge, parmesan cheese, and parsley on top.