2 celery stalks, cut lengthwise, sliced on angle 2 medium onions, peeled and chopped 2 tablespoons butter 1 quart chicken stock black pepper, add to taste 1/2 teaspoon thyme 1 1/2 pound potatoes, diced, skin left on 9 tablespoons butter 1/2 cup flour 1 quart half and half 1 quart whole clams, course chopped 2 cans (6 oz size) clams, minced 1/4 cup sherry 1/4 cup fresh parsley, chopped, for garnish
Sauté celery and onions in 2 Tbsp of butter for 10 minutes until opaque. Add to chicken stock in large saucepan. Add the juice only from the clams, reserving the meat.
Bring mixture to a low simmer; add pepper and thyme. Add the potatoes and simmer until cooked but still firm. While the potatoes are cooking in the soup, warm the half-and-half.
Make a roux with the 9 Tbsp butter and 1/2 cup flour; when cooked, add to the half-and-half off heat. Stir until well blended; return to the heat and stir until smooth and thickened. Set aside.
When the potatoes are just tender, add the clam meat, cook for 2 minutes then add the half-and-half sauce. Simmer for 8 minutes then add the sherry. Simmer for 2 minutes more, garnish with parsley and serve.