Add the potatoes, water, ham, celery, garlic, and onion to the stockpot. Bring to a boil and then simmer over medium heat until potatoes tender (10 to 15 minutes). Stir in the chicken bouillon granules, black pepper, and salt.
Melt the butter in a separate saucepan over medium-low heat. Add the all-purpose flour and cook and stir until thick, for about 1 minute. Cook and stir until thick, 4-5 minutes.
Pour the milk mixture into the stockpot and stir until warmed through.
Serve hot and enjoy!
