Begin by heating a large pot over medium heat. Add diced bacon and cook until crispy and golden-brown, about 5-7 minutes. Transfer bacon to a plate to drain excess grease, leaving drippings in the pot.

In the same pot with the bacon drippings, add chopped celery, onions, carrots, and red onions. Sauté over medium heat for about 5-7 minutes until softened and fragrant.

Stir in a bay leaf and all-purpose flour, cooking for an additional minute. Ensure to stir continuously to prevent lumps from forming.

Gradually whisk in chicken stock and condensed cream of chicken soup, until smooth. Keep the heat on medium until the chowder begins to simmer, about 3-5 minutes.

Lower the heat and mix in cream cheese, milk, and heavy whipping cream. Stir until well combined and cream cheese has melted, about 3-4 minutes.

Stir in frozen corn, cooked turkey, shredded hash brown potatoes, turkey gravy, and dried parsley flakes. Cook gently for 10-15 minutes on low heat until heated through and creamy.

Remove and discard the bay leaf. Ladle into bowls and sprinkle with chopped green onions if desired.