Corn Chowder (knock off from Mimi's Cafe)

4 tablespoons butter or margarine
6 tablespoons onion, chopped
3/4 cup celery, large diced
2-1/2 cups hot water
2 cups raw potatoes, peeled and cut in 1/2" cubes
1 quart half & half
3 cups frozen corn, thawed
2 tablespoons sugar
2 teaspoons salt
1 pinch white pepper
1/2 teaspoon cayenne pepper
3 tablespoons flour

On medium heat, melt butter and simmer onion and celery for 5 minutes until soft, but not brown. Add water, potatoes, corn, and seasonings. Cover and simmer for 30 minutes, or until potatoes are barely tender. Whisk the flour into 1 cup of the half and half, and stir into the soup. Add the remaining 3 cups of half and half. Simmer for about 15 minutes, until the soup has thickened to a creamy consistency. Add cayenne pepper, salt and pepper to taste. To make the soup thinner, add a little milk. To make the soup thicker, simmer another 5-10 minutes.