In a large stockpot over medium heat, combine the onions, celery, carrots, and butter. Sauté until the vegetables are softened. Add in the garlic and parsley, sauté until fragrant, around 2 minutes. Sprinkle the parsley and thyme over the vegetables and mix in.

Sprinkle the flour over the vegetables, stirring into the butter. Cook for 2 minutes until the flour smells nutty and is slightly browned.

Slowly whisk in the chicken broth, making sure there are no lumps. Add in the corn, creamed corn, potatoes, and then salt and pepper to taste.

Bring to a low simmer and cook until the potatoes are tender and falling apart. Stir in the cream, whisking to ensure there are no lumps. Add in the cooked chicken. Cook for another 2-3 minutes.

Remove from the stove and ladle into bowls to serve. Top with minced green onions if desired.