Peel and dice the potatoes into small cubes. Chop the carrots, celery, and onion. Mince the garlic and dice the chicken into bite-size pieces.
In a large soup pot or Dutch oven, melt the butter over medium heat. Add the diced onion, celery, and carrots. Cook for about 5 minutes, stirring occasionally, until the vegetables begin to soften.
Stir in the minced garlic and cook for 30 seconds until fragrant.
Add the diced chicken to the pot and pour in the chicken broth. Stir well and bring the mixture to a gentle boil.
Add the diced potatoes and thyme. Reduce the heat and let the soup simmer for 20 minutes, or until the potatoes become tender and the chicken is fully cooked.
If you prefer a creamy chicken potato soup, stir in the milk or heavy cream and cook for another 2 to 3 minutes.
Season with salt and black pepper. Ladle the soup into bowls and garnish with fresh parsley before serving.
