Add the potatoes, water and Herb-Ox to a medium pan and bring to a boil. Boil the potatoes for 8 minutes, or until tender. Drain the potatoes over a large bowl to save the cooking liquid - this will be added back to the chowder. Set both the potatoes and liquid aside while preparing the rest of the chowder.

In a large pot, cook the salt pork over medium high heat to render 1/4 C fat. When 1/4 cup of fat is rendered, remove the salt pork from the pot and discard. Lower the heat to medium and add the onions and celery. Cook for about 5 minutes or until softened.

Stir in the flour to coat the vegetables in the flour and cook for 1 minute. Stir in the clam juice, reserved potato cooking liquid, bay leaves, thyme and white pepper. Simmer for about 5 minutes over medium heat until the soup thickens. Stir in the clams, potatoes and half and half. If you want a thicker chowder, stir together the cornstarch and water to make a slurry. Stir the slurry into the chowder until it reaches your desired thickness. Simmer for another 5 minutes but do not let it boil. Serve immediately and refrigerate leftovers.