Step 1

Pre heat oven to 350 degrees and place rack in center of oven.

Step 2

Grease a 9x13 or 4 quart casserole pan.

Step 3

Place the grated potatoes into the pan. The amount of potatoes should equal about 6-7cups.

Step 4

Sprinkle the chicken over the grated potatoes in the pan, set aside.

Step 5

Melt the butter in a large saucepan. Add the chopped celery, onions and carrots. Cook over medium high heat for about 4-5 minutes or until the vegetables are tender.

Step 6

Add the salt, pepper, poultry seasoning and dried tarragon leaves. Sprinkle with flour and mix well until flour disappears into the butter and vegetable mixture. Reduce heat to medium and cook for about 1-2 minutes.

Step 7

Add cream cheese to pan. Mix until cream cheese melts.

Step 8

Add milk, a cup at a time, waiting for sauce to thicken a bit after each addition. Use a large whisk to stir the sauce and smooth out any clumps of flour.

Step 9

When mixture is thickened and bubbly, add chicken broth a cup at a time. Cook for an additional few minutes. Taste sauce and add salt and pepper if additional flavor is needed. Add a few drops of hot sauce.

Step 10

Pour the sauce over the potatoes and chicken in the casserole pan and top with grated cheese.

Step 11

Bake for 30 minutes, uncovered.