Piatt's Tea Room Fried Chicken

6-8 bone-in chicken pieces 1/2 tablespoon chicken soup base1 onion, coarsely chopped3 ribs celery, coarsely chopped, or 1 teaspoon celery seed1 teaspoon salt1 teaspoon pepper4 tablespoons butter 1/2 cup olive oil1 egg 1/2 cup unflavored bread crumbs1 cup flour2 teaspoons sugar 1/2 teaspoon salt 1/2 teaspoon pepperGravy 3/4 cup reserved broth1 cup milk2 tablespoons flour2 teaspoons sugar1 teaspoon saltIn 6-quart pot, place chicken pieces and cover with water by 2 inches. Add soup base, onion, celery, salt and pepper. Bring to boil and simmer about 25 minutes to parboil; not long enough that the skin and bone are falling off. Set aside to cool. Remove skin if desired. Reserve 3/4 cup chicken broth for pan gravy.Heat 12-inch cast iron skillet over medium-high heat and add butter and olive oil. Beat egg in large mixing bowl, set aside. In a second bowl combine bread crumbs, flour, sugar, salt and pepper. Coat each chicken piece with egg and dredge in the bread crumb and flour mixture. Gently place each piece in the oil and butter, adjusting the temperature higher if needed. Beware of popping oil. Fry chicken in batches, about 3 minutes or more on each side or until light to medium-dark brown, as desired. Blot the pan with a paper towel to remove excess oil, but don't scrape it clean. For the gravy: Heat broth in the skillet, stirring up browned bits with a spatula. In small bowl whisk together milk and flour until very smooth. When broth begins to simmer add milk/flour mixture and stir continually until it thickens. Add sugar and salt; adjust to taste.Serves six to eight. Nutrition values per serving: 258 calories, 14 g fat (4 g saturated), 10 g carbohydrates, 1 g fiber, 22 g protein, 99 mg cholesterol, 747 mg sodium.